Just like the Gamestop employee who claimed Fallout 3 had a great story with great characters, but New Vegas didn't. This person didn't have a sloped forehead btw. He actually found the story in New Vegas to be boring with no interesting characters. I went on to explain how the faction system worked, but his brain seemed to shut down because he just kept shaking his head no, like the possibility of New Vegas being a better game was too much to bear.
Actually a coworker of mine prefers Fallout 3 to New Vegas and his description leads me to believe that it's because of the strong main story line in Fallout 3. That is strong in the sense of being a clear, central drive to the game that carries you from area to area, not that it was good. I've avoided Fallout 3 but New Vegas is crap as far as I'm concerned. There is too damn much walking, combat is crap, and the writing wasn't particularly captivating. It doesn't help that a number of quests make you do excessive amounts of walking between characters and places. I'm patient to a point but one of the worst things in games, MMOs do this a lot, is long stretches of traveling. I enjoy exploring interesting worlds but the world of New Vegas is mostly uninteresting. I doubt Fallout 3 is much better in that aspect but a number of players do better when their wondering is to unveil an expanding central plot rather than a bunch of small stories. I'd wager that New Vegas does a much better job of having all of the events tie into the world rather than offering a bunch of self-contained amusements but it still doesn't add up to enjoyment for me. I also think that a lot of the enjoyment in those games comes from just enjoying going out into the wilderness and blowing away baddies, something which doesn't interest me if the mechanics aren't there to make it interesting.