In the weeks before FO:NV shipped, I asked in several posts (here and there), for a developer to give a demonstration of VATS, that highlighted the positive benefits of using it's various targets.
At the time, every video released that had VATS, showed the devs' entering it and doing headshots ~exclusively.

Can anyone demonstrate why you would benefit from attacking any other limb than the head on FO:NV? In the previous games [1&2] crippling the leg(s) had a devastating effect on movement, and crippling the arm would restrict enemies from using two handed weapons (like hammers and rifles) ~Cripple both arms and they could not use weapons at all. Fallout 3&NV do not allow groin & eyeshots, but those could result in knockdowns, knockouts, (or even instant death in the case of the eye or head). I don't notice much effect from limb hits in the game (other than a cosmetic limp for the legs).
I was just curious, because I don't recall seeing a single instance where a developer chose anything but a headshot.

Depending on what is happening in the game world, various VATS targetting will have higher percentages on areas other than the head - blocked line of sight, movement etc. Shooting weapons out of enemies hands, shooting explosive weapons, crippling limbs on fast moving enemies, chest shots giving knockdowns.

There's a range of options...

Can you no longer shoot a deathclaw in the leg to slow it down? That was a tried and true survival tactic in Fallout 3 if you didn't have a dart gun handy. There's also a Guns perk that gives bonus damage to torsos. Actually, Fast Shot is kind of a fun trait to take for a VATS-based character, as it makes weapons cost fewer AP, and it reduces accuracy all around so shooting arms and stuff ends up being a preferable alternative to always getting in close for the head shot.

I usually go for head shots because it does the most damage. Why cripple your enemy when you can just kill him with less ammo?
That said, when up against a particularly strong opponent I may cripple a leg so that I can more easily out maneuver them (especially against super mutants with melee weapons). I rarely shoot arms and if I do its so they drop a weapon for a moment. I never play the long strategy attacks of crippling enemies piece by piece because fights tend to end fairly quickly with only a few exceptions.

Strategy is used to fill the gap between your strengths and the strength of your enemy but need only be applied when the enemies strength is greater than yours. At least thats how I play in the game. Would never neglect strategy in real life (too much loss and too much chance of failure to take anything for granted.)

What does crippling the leg really do? I've seen the limp (I actually thought about using the deathclaw limp animation as the regular walk because I liked the way it looked better than the healthy walk).

It was a tried and true tactic on FO1 also... I never noticed any real benefit of shooting the leg in FO3 (not to say there was none(!), but I just never noticed it... unless maybe it just meant that they could no longer catch you if you ran).

*Edit: I didn't know that about Fast Shot... I assumed that it would prevent using VATS altogether.

That's how I play the game.

I remember back in Fallout 3 it was difficult to headshot supermutants and mirelurks, so it was best to target limbs instead. It was especially hard to head shot supermutants when their back is facing towards me, because they just have massive shoulders, and the head is well concealed.

In New Vegas, everything can be head shotted easily.

I saw... That's all they did in VATS.

**Anyone know if VATS is hardcoded, or if its a script? (I guess I'll ask that in the GECK thread.)
*I'd like to peek into it if its a script.

Crippling an enemy's legs is a sure-fire way of neutering enemies that could otherwise outrun you - primarily Deathclaws and Yao Gui (in 3). A deathclaw without its leaping attack is far less dangerous. Also, it renders an enemy's attempts to flee as somewhat useless - no more running away with my loot!

Shooting an enemy's weapon was a vital survival tactic in the 3rd game when playing on very hard mode. Super Mutant Overlords etc. could kill you in two hits with a gun, but reduce them to fighting with their fists and they were much less dangerous.

But yeah, 99% of my general VATS shots are aimed at the head, the other options are only useful in certain situations.

Same here (at first). Though I picked up on the fact that any limb dropped to zero kills, so now when I play I generally shoot for the weakest limb.

(hold on... I may actually have it wrong... even though I do shoot for the weakest limb.... Last time I played I shot a super mutant in the arm and he died, but it may have just brought him to zero.)

*I'm still just out of Nipton in this game, so I'm still searching out the differences.

There definitely are benefits for aiming at limbs other than the head, it just depends on what you're fighting.

One thing to keep in mind is that VATS no longer provides such a massive defensive bonus (you still take 75% damage if struck during VATS). If you're engaging multiple targets, that means there are times when shooting at limbs that will reduce their damage output immediately will be the superior option, unless you have a similar chance of instantly killing one or more of those targets.

Aside from that, you just need to consider what you're fighting. Deathclaws, for example, are fairly tough to kill when strictly using VATS. You're rooted in place during a VATS sequence and their defenses are such that you aren't terribly likely to kill them immediately with a headshot. Because Deathclaws are incredibly fast, this allows them to close distance with you, which just puts you in a situation where if you can't create more distance, you're going to get mauled. If you're forced to engage Deathclaws at anything closer than "long" range, attempting to cripple one of their legs will not only slow them down by a huge amount, it prevents them from using their powerful lunge which seems to clear about 5 yards. It makes killing them a much safer endeavor in general, as even a slower moving player (say lacking AGI or wearing medium/heavy armor) will be able to outrun them.

Cazadores are another example of an enemy that is only really deadly because of extreme mobility. By aiming for the wings, you can cripple them and force them to close distance by crawling on the ground in stead of flying, which again makes them far easier to outmaneuver. Really, anything that is forced to engage you at melee range is significantly less threatening when you cripple their mobility.

As far as humans go, headshots are clearly the most damaging attack, but you also should consider just how armored the person is. If they're wielding a high powered weapon and you can't guarantee a one or two shot kill (whether because of their armor or because of the lower chance of actually hitting their head at current distance), shooting their arm instead will often cause them to drop the weapon, giving you more time to make a kill while removing the threat of damage against you entirely. You also might consider simply shooting the weapon itself if it is large enough, which will actually break the weapon completely and force them to either find another weapon in the environment or switch to something else (which is almost always a good thing as they will typically default to their most powerful weapon).

Against certain robots or insects, another good option is to aim for the inhibitor or antennae, as it will cause them to enter a "frenzy" state, basically making them hostile to all targets nearby instead of just you and your companions. A good option when there are multiple targets as it can both help you kill the other targets, and draw fire away from you onto the frenzied enemy.

There have been quite a few times when using VATS for a head shot wouldn't work so well. There seems to have been some thought put into the environment, because I have had baddies come at me and have environmental object block their heads. I may make my moves from crappy angles too. In those situation I'll go for the leg or the weapon. But, like previously said, most of my shots are at the head.

That's exactly what I wanted to know... and VATS is sounding better.

I did not know that Cazadores crawled with crippled wings. (and that's a nice touch)

I still use arm shots if I know I'm not going to kill with headshots or I'm especially scared of their weapon. It's a flamer and they're right on me? You're dang straight I'm aiming for either his gun or his right arm.

I only shoot legs when they run away.

Enemies are always so squishy that shooting out their arms or legs is useless. In 1 and 2, sometimes enemies were really tough and if you let them get some hits on you, you were done. Crippling a leg against a tough melee opponent or an arm for a two handed weapon wielder would give you free shots on this enemy who would be doing just as much damage to you as you to him otherwise. That was the tough part of combat in the old games - Enemies were pretty much just as strong, if not stronger, than you! You couldn't just jump in against 6, 7 enemies easily.

In New vegas, your average human opponent will die with a couple shots. Even the tougher ones, I never felt the need to cripple anything. Hell, I barely ever used VATS, I found the FPS-style combat very responsive and fun.

I'm a big fan of shooting weapons, although if I don't want to damage the weapon crippling arms is a good alternative; I haven't done this as much with FONV but it was effective in FO3. Crippling legs doesn't do much unless they're extremely mobile - it's not bad when an opponent has lots of cover but I find arms are still the better target.

VATS does seem to be biased towards headshots, I would have liked a perk that made it easier to target/cripple limbs as I think this would have made them more appealing. There are some weapons geared towards this but they tend to be melee weapons so VATS is less important.

If it has already been said, shooting off the antennas of insects makes them frenzy and attack other insects. It makes for a nice show. You will know if you do it, just take one shot at a time so you don't kill it on the 2nd or 3rd shot. I was able to shoot dynamite in a Powder Gangers hand before he could throw it with nice results. I also like to shoot the melee weapon out any fool that tries to rush me and let Veronica practice decapitating their heads. They say you can shoot tossed grenades or dynamite and not get hurt but I have not had the chance to try it.

There is a perk that increases criticals when you aim at the same limb. I forget what the name of the perk is. I know you can get it around level 10 or 12 at least.

What kind of f*cked up person would fire at someone's groin or eye anyway?

To be honest with you, the only time I aim for anything except the head in VATS is when I have a better chance of hitting a different limb other than the head. This situation pops up frequently because the bad guys aren't always close enough for a 95% shot to the head (it's the most penalized to hit), or they are posed in such a way so that their head is obscured and thus the chance to shoot them in the face is severely penalized.

You're thinking of Concentrated Fire, but what it actually does is increase your hit chance with every VATS attack you queue up beyond the first on the same limb within the same VATS sequence.

Basically, if you have enough AP for say 6 shots and your hit chance on their arm is only 60%, the second attack you queue up on the arm will have 65%, the third will have 70%, the fourth will have 75% etc. This resets each time you exit VATS.

If you don't want an enemy to get away, take out their legs. Hell, the game even tells you that during some load screens.

When fighting human enemies, or humanoid enemies, I more often than not go after the headshot, if I'm using VATS.

HOWEVER, I do aim for the wings of Cazadores and the stingers/tails of the Scorpions. Note that neither actually have the ability to aim for the head in VATS. Well, you can for Cazadores, but I've found it's a rare scenario, usually when they're close by and/or when they're about to sting. Anyway, aiming for their wings slows them down, which is beneficial.

I use V.A.T.S. to shoot grenades/dynamite in peoples hands.

@PowderGanger - I would, if the groin shot did not kill them, it would definitely stop them in their tracks Then again, I am just evil like that sometimes..

The original Fallout had eight targets (when shipped ~http://i271.photobucket.com/albums/jj125/Gizmojunk/Fallout-1.jpg). The eye and groin were selectable targets with certain critical effects.
(for instance an enemy could be blinded, or a critical groin hit could make them pass out).