I think a lot of people forget one thing: intelligence is basically as good as the info you're putting into it. So even if you have a tremendous AI, it can only be as smart as the info it can access. It could only have god-like powers in realms from which it could extract some information. It's still very much subject to being blinded by ignorance (in the most literal sense of the word).

But I do agree that, if it has complete information, an AI could potentially beat us at anything that requires thinking.