Well, im going to pick up Fallout 3 GOTY AND Fallout new vegas. Im looking forward to it but my friend told me that you cannot carry on after you complete the main quest. When i heard that, it was a massive let down ): But i also heard that they patched it up so u can carry on the adventure after you complete the main quest.. Which one is True or False??

If FO3 has Broken Steel DLC, you can carry on but New Vegas you can't. Just don't make a big deal of the New Vegas one, Ive seen my share of people complaining about it on the forums and they get yelled at for it...

You can′t continue after you completed the main quest, due the many different outcomes of the endgame. Obsidian has also stated that it wont happend.

ok then, thanks

This is a non-issue in NV- there is a LOT to do in the gameworld without ever completing the 'main' quest. Plenty of sidequests and adventures and exploring to do. And you can do 95% of the main questline right up until the beginning of the final battle sequence, and still keep doing anything else you want to in the game. It's just after you initiate the final battle, that you get a warning message telling you if you continue, you won't be able to go back or keep playing after you do. At that point, you can keep going, or choose 'no', and put it off till later. Or you can do a save at that point, finish the endgame quest, then restart from your save and go about your business. Or, as many people do, finish the main quest, then start a new, mo bettah character and do it all again, and catch all the things you missed on the first run through. It really is no big deal.

Fallout 3 GOTY you can follow on from the end with Broken Steel. It loads automatically when you finish the last part. Fallout New Vegas has the very big oversight of not being able to continue on after you finish. I see no reason why they could'nt have made it so you continue on after the end with dlc like F3.

They wanted the game to end when it did, same way an author finishes his/her book when they feel they're done. Simple, really. If you don't wanna end your current playthrough, don't finish the main quest. Besides, NV changes things more dramatically than FO3 did, even though they sorta toned down the influence of the new fresh water... though it was more realistic... anyhow, I ramble.

Before more people post I'd like to state that this subject has been discussed here countless times.
So let's stop beating the dead horse shall we? I think the answer to op's question is already given.

The reason I'm writing this is because I've seen many innocent threads turn into rage wars.