Well, there are other things to consider when talking about how much longer the consoles should be used. For instance, the disk drive in the PS3 is really too slow. It might have the power to last another 5 years but load times will just get worse as it ages. On the Xbox side, Microsoft made the mistake of using dvds which means you're already seeing 2 and 3 disk games. Five years later you could be buying 4 or 5 or even 6 disk games as they continue to grow.
I think the big advantage to new consoles is the headroom it would give developers to work with and allow them just that extra push. It could allow for things like an increase in the size of multiplayer games, or how realistic the physics can be.
I won't say that the current consoles are outdated, but I also won't say that a 2013 release of the new consoles would be too soon.







