I was surprised that Hulk had the funniest moments
I also like the new Banner, the previous Banners (and Hulks) didn't seem to have any humour.
I watched it in 3D but I wouldn't recommend it. I didn't think it enhanced the movie at all, in fact it made certain parts of it difficult to read (but that's probably my fault for "losing" the 3d focus during the action...)
I watched avatar in 3d as well and I didn't even feel that was impressive (but I did notice that it was done substantially better than avengers :p)
Meh, think I'll just stick to 2D in the future. Better (for me) and cheaper!