One of the most overrated was The Dark Knight. Good in its own way you understand, but nowhere near deserving of the hype.
I still say Heath Ledger's better role was in Brokeback Mountain, though others might disagree.
And Christian Bale is not the best Batman out there. There are much better in the last two decades. Except for the one with the bat-nipples in the batsuit...
[Edited by Paradox, 4/2/2010 2:24:07 PM]