Well, I'm not sure about how you're judging 'power' but yes history shows simply having 'power' doesn't mean win for consoles.
What I find interesting with PS3/360 is they seem to have pushed console power the most compared to PCs. As such I feel both were 'too' powerful to have much chance of winning when they launched, and that both are actually gaining a fair number of ex-PC players rather than scoping up lots of PS2 owners. Judging by sales many of those have gone with a Wii or are still on their PS2.
Try to be reasonable... its easier than you think...







