Anyone else disappointed with Fallout 3 in the end?

[Crusader]

I liked FO3, but I was surprised when the game ended. I was like "What, already?" The ending in itself was not bad. The little stroll you make with the brotherhood's toy was pretty awesome. All I really missed was a final boss. The previous games had a big, bad evil dude that took a lot of effort to kill. Not so in FO3 where the final guy you kill is interesting, but far from uber (in fact, he died in 2 seconds). Hence I was surpised when the game was over. Even if you do not die in the end, you can't play on.

So I'm hoping for an expansion. I need more quests!