Really depends on how long Sony is going to keep the PS3 out. MS won't keep the 360 out for too much longer. They have an opportunity in the next couple of years release a new console and really take off much more than they ever can with the 360. So if Sony decides to not release another and go with the 10 year cycle they could simply pass them by default.
Wii pretty much has it in the bag. Even with sales down they are still outselling the competition so not too many worries. 360 and PS3 could switch spots but I doubt it.
Personally, I think people really missed what happened at E3. When they saw things like NATAL and Sony's motion controllers they really just saw them advancing technology or catching up. What they didn't see is that they are preparing for their next consoles. They aren't just showing that to help a PS3 or 360 compete with Wii. They are showing this to make a point that they are ready to move on. Next generation could be hear quicker than we all think.
