An emulation not working at full speed is always possible. You could emulate the PS3 on a 386 @ 25 MHz if you wanted to (provided you had a 512 MB hard drive to store the PS3 RAM on :P).

True. Anyway, using the same processor architecture at comparable speeds should ensure better performance, so that even if gaming wouldn't be possible, the other purposes should be satisfied in a usable way, while having an emulation really unbearably slow should defeat also the other purposes, as even if theoretically it would be a working emulation, time at disposal of people using it isn't unlimited.

I'm curious about how good these emulators will be, either qualitatively and quantitatively, if someone will really develop them, naturally.

I lol'd.