I am by no means an expert on the subject. But since everyone else is doing it, I thought I share my 2 cents on the matter anyway.
Much speculation about AI revolves about super intelligent beings of awesomeness. But it's unlikely that mankinds first sapient and sentient artificial intelligence will be as or even more clever than the average human. This could be for any of these reasons: Limits in hardware, limits in it's implementation and of course limits imposed on it by us.
An easy to imagine example would be the AI resulting from a emulated human brain. It might be as intelligent as us in principle, but it might simply not run as fast. Or the emulation could be imperfect and introducing either defects or slowdowns that way.