EDIT: Please look at the bottom of my post, I have made a mistake and there is most likely no new attachment at all, my apologies.
So I was watching http://www.youtube.com/watch?v=Odefa3EgTpM#t=4m6s (General Gameplay) frame-by-frame, and I saw http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol2.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol.jpg with what looked like a tactical light attachment, naturally I immediately thought of the
http://brink.wikia.com/wiki/Sea_Eagle_Pistol
So I checked the video where I first saw the Sea Eagle: http://www.youtube.com/watch?v=tI4y2P0r7K0 To my surprise I saw that firing the Sea Eagle does not make the slide (or priming mechanism) go back like the pistol in the new video:
http://i1132.photobucket.com/albums/m574/Jaina_SoIo/pistol1.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/Pistol2.jpg

http://i1132.photobucket.com/albums/m574/Jaina_SoIo/SE1.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/SE2.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/SE3.jpg

So I checked the E3 video for http://i1132.photobucket.com/albums/m574/Jaina_SoIo/e3weapons.jpg of all the known pistols:
As you can see there are 5 pistols: 3 handguns, 1 machine pistol (seen here), and one revolver.
The 3 handguns (from left to right) are the Kolt, the Sea Eagle, and an Unknown pistol.
Now the video is obviously not the Machine Pistol, or the Revolver.
However it can’t be the Sea Eagle either, because of the aforementioned recoil differences.
This leaves us with these options:
1. The Kolt Pistol
2. The Unknown Pistol
3. Another pistol that we are unaware of.

It could be the http://i1132.photobucket.com/albums/m574/Jaina_SoIo/Kolt.jpg because the firing animations match up (both push the slide backwards).
It could be the http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol4.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol5.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/Unknownpistol6.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol7.jpg

However, which pistol it is in the video is slightly irrelevant, the Important thing is: (excluding the possibility that it is in fact a new pistol) 1 and 2 are the only possible conclusions, however neither of these have a tactical light by default in either of http://i1132.photobucket.com/albums/m574/Jaina_SoIo/Kolt2.png http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol4.jpg

Unless I’m missing something, which is entirely possible, the tactical light must be an attachment, which begs the question – is it functional? Does it produce a light similar to a flashlight, or is it more like a laser pointer?
If any of you have an opinion, feel free to let me know what you think.

Oh, and just to let you know, I would gladly accept a certain shelled reptile if I were given one :whistling:

EDIT: After obliviondoll posted I decided to investigate further and it seems that the pistol in question is indeed a Sea Eagle as the trigger guard is far larger than the one on the http://i1132.photobucket.com/albums/m574/Jaina_SoIo/Kolt9.jpg and lacks the distinct sharp edge found on the http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol4.jpg, however comparing these http://i1132.photobucket.com/albums/m574/Jaina_SoIo/SE6.jpg http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UP11.jpg it looks like the trigger guards are perfect matches, so it seems that I did not discover something at all, oh well.

I suppose a moderator can lock this topic and/or give me a turtle.

it might be a flash light, you can see it on other guns in vids here and there and there are dark night maps. there even appears to be one on the gun in the middle of the screen.

WHAT? WHERE?!

http://www.youtube.com/watch?v=oDz8bC3Ljk8&feature=related, but you can see the night sky, also i would assume there would be some levels that have dark areas in doors or underground

hope its a flashlight that would be badass.

Lasor sight would be awesome...
My bet is a flash light though.

You're missing a possibility...

The animated mechanisms could be a later addition to the game. It could still be the Sea Eagle, but the slide has now been animated.

Either this, or the resistance and security versions are just animated differently. Looks like a sea eagle to me.

A laser would be a nice addition for pistols though. It could make hip-firing more accurate

That's possible, however I would think that if they are adding animations, than the Sea Eagle would not have an animation to begin with and would stay in it's position while firing.
Although it is possible that they replaced the recoil animation with the sliding animation.

They have really kept us waiting too long... some of us are truly obsessed with this game. - Myself included.

The madness is contagious.

animating the gun and animating recoil on the player are potentially completely different. That could just be the generic pistol recoil you're seeing in the older video, with the variable higher than normal.

ha ha. I will give you a turtle: :turtle:
I've wanted to do that. now my time on this forum is complete, or rather it would be if I got a turtle. lol

here lolz :turtle:

The amount of links on this thread hurts my feelings.

http://www.halolz.com/wp-content/uploads/2009/03/teamfortress2-300sparta.jpg ... Sorry, I had to.

On topic; I find it interesting people go through videos putting forth so much effort and attention to detail trying to find new things. Admittedly I'm too lazy. I'd rather sit here and wait for someone else to point them out, lol. Nice find. I'm intrigued.

Just attach a duck to the side

Thanks!

Thank you. And you're welcome Jaina.

http://i1132.photobucket.com/albums/m574/Jaina_SoIo/UnknownPistol.jpg

This is the best picture that OP provided, and with it you can see that it has the exact same shape as the http://images2.wikia.nocookie.net/__cb20110405203030/brink/images/8/8e/Sea_eagle_2.jpg, and does not resemble any of http://img219.imageshack.us/img219/5782/brinkweaponspage30.jpg at all. The fact that the flashlight is there kinda seals the deal.

The flashlight seems to be a part of the gun, and not anything useful, like the kross. It will probably be replaced if you put any bottom attachments onto the gun. Flashlights have no purpose that I can think of in the game, since all the maps (even the night ones) are illuminated well enough to see.

Laser sights, on the other hand, I expect to see in the game.