I watched The Hangover about a month after it was released. By that point, I could not get away from the incessant praise from everyone I knew, saying how hilarious it was. So I came into it with high expectations, but I laughed only a few times. So yeah, it's really unfortuate that my expectations were so high, because whenever I have high expectations, they're almost never met. I couldn't get away from all the praise though! Every magazine, every internet article about the movie industry, every facebook status, it was all about how well it was doing at the box office and how funny it was.
Up is another one I find a bit overrated. If I have to be honest, I enjoyed The Princess and the Frog more than Up. But Up was still solid, and it's a shoe-in to win Best Animated Picture and to get nominated for Best Picture. I just wish TPatF would have that recognition.
I just watched The Hurt Locker, and I think I might have liked Up in the Air better. But that's just because I usually like drama/comedy films more than straight-up action flicks. THL was still very good though. It was well-acted and very realistic. I just really liked the ensemble of UitA, and its message was nice. I would be glad to see both of them win, but I'll give the edge to THL since it's a strong, solid piece of work.