I think next year we might enter the twilight of Wii's life span-but I think that twilight will be the best part of Wii's lifespan in terms of quality. I expect that twilight phase to last until the end of 2011, or 2012 before a new Nintendo home console comes out. The fact is, Wii could still be a viable platform in 2012 or 2013, and we might see some games that push the hardware in amazing ways even when Nintendo's next home console is on the market.
As it is, I don't think Microsoft or Sony can jump ahead and push a machine out before 2012. They've lost so much money on PS3 and 360, I don't see how they could justify pumping even more money into their videogames sector when other parts of their business are facing stiff competition. Apple gives MS and Sony cause for concern, Google is a big threat to MS, Sony faces tough competition in virtually all of its consumer electronics markets. Neither company has the financial muscle to launch a machine within the next 3 years. They're relying on a long console cycle to recoup at least some part of their losses before launching a new machine.
Nintendo, on the other hand, has generated massive profits and introduced many people to videogames. They've created a highly popular brand that should serve them well in the next generation. But do they want to squeeze the Wii for every penny of profit, or are they going to push out a new home console before their competition can respond? Perhaps they could manage both. It's difficult to tell. Apple, Sony and MS are all gunning for a piece of Nintendo's pie, which is virtually an industry in itself. I genuinely don't know what Nintendo will do.
I do, however, expect the next couple of years to be filled with quality titles on all 3 machines. There are big gems coming in the near future-Galaxy 2, Metroid Other M, GT5, FFXIII, Mass Effect 2... And the biggest gem of all (for me) is just on the horizon-Zelda Wii. Who knows what could be beyond that?
Perhaps instead of speculating what hardware comes next, we can continue to enjoy the great software we're getting. That's what I plan on doing.
This generation doesn't end until I say it ends. 