The thing to remember before claiming that graphics can't get any better is that we thought that before (at least I did). I never had a problem with the way my N64 looked until I played GameCube for a few years. And until I saw the first 360 footage, I didn't think graphics could get any better than the Xbox.
Predicting the future is hard, hard work, and is ultimately only useful for some interesting forum discussion. No one thought that Nintendo would come up with DS or Wii, and look at how they changed the market. As Henry Ford said, "If I asked my consumers what they wanted, they would have said a faster horse." The Big 3 (and maybe some others) have been hard at work thinking of new console ideas since '06 (or in Microsoft's case, '05.) We'll probably see some teasers in the next year or so, because even if there are no improvements to be made, consoles are so profitable right now that companies will still keep trying for a while before giving up.
Predicting the future is hard, hard work, and is ultimately only useful for some interesting forum discussion. No one thought that Nintendo would come up with DS or Wii, and look at how they changed the market. As Henry Ford said, "If I asked my consumers what they wanted, they would have said a faster horse." The Big 3 (and maybe some others) have been hard at work thinking of new console ideas since '06 (or in Microsoft's case, '05.) We'll probably see some teasers in the next year or so, because even if there are no improvements to be made, consoles are so profitable right now that companies will still keep trying for a while before giving up.