Looks exactly like the other games.
I guess a nuclear wasteland can't look much different, but they'll have to change something to not make it like the last two.
You could argue that fallout is just oblivion with guns and NV is oblivion with guns with a sepia filter. A game doesn't have to 'look' different to 'feel' different.
Hell just look at some of the expansions you got with New Vegas - Dead Money and Point Lookout. Gave the game totally different vibes and introduced some new gameplay elements, not to mention the stories within those we're pretty dope as well.
