I got my game yesterday and installed it, and after a little issue with Steam I got it installed and running fine. I played NV for 2 hours with no crashes or bugs, but when I went to exit the game and clicked "Exit Game", the whole thing just locked up and crashed, I had to turn it off using task manager. I tried exiting the game multiple times and each time it crashed. I reinstalled the game, but to no avail. My OS is Windows 7 64bit, is anyone else having this problem, and if so is there a solution? Please fix this in the upcoming patch.
Sorry but, good luck. Fallout 3 has been doing that for 2 years now.
If it makes you feel better it's happening to me too. =)