Yes, but in fairness - he was directed to play a campy, humourous Batman with various one-liners thrown in for good measure. In a shiny Batman suit with nipples. The script and storyline were both written like a light-hearted comedy rather than a dark and brooding film like Begins.
Clooney has shown that he can do dark material and be serious (just look at him in Syriana, does he smile once?) ......... so I think he could have done Batman justice if the film had been directed that way.
Gaz