I think that 88% is just too far out of proportion to give it equal weight (a VERY different era, and smaller bases often lead to exaggerated percentages). Even the 50% of the 5th gen is a tad high - it's "new" gamers were basically then-traditional gamers that were out of high school, so they were already "game friendly" and easy to tap. The Wii's growth is into a completely alien demographic, and should therefore expect much higher resistance. A growth of around 30%, to 250m, seems far more plausible (unless multiple console homes becomes a much bigger factor, which is possible).

On the future?

The Wii? It's doomed. A Wii2 will come out in 2011 at the latest, and Nintendo, not being stupid, will do all it can to push the Wii market to the successor (which will almost certainly be BC) so it's sales won't be cannibalized ala the PS2/PS3. I'm not sure that the Wii2 will make any more radical improvements, but it will certainly refine what works now.

Sony and MS have to be a bit worried right now - the Wii has completely upended prior beliefs about what a "next gen" console must be like. And if they think developers are complaining about high development costs now, what do they think will happen if the PS4 and XBox720 "improve" by another order of magnitude? Honestly I expect those consoles to focus less on improved horsepower than on added features. I don't expect either to push the price margins again (esp Sony), and they may not even go with multiple price points this time (has that really helped anyone?). And just as the Wii2 will incorporate high-def, the Sony and MS consoles will have to incorporate motion controls or something similar in their nextgen conoles.

That's exactly why I think the Wii2 will be yet another unique experience, a la DS vs. GBA.

When Nintendo released the DS, they specifically stated it was not a successor/replacement to the GBA, but instead a "third pillar". They continued supporting the GBA for quite some time, but obviously just to satisfy people who didn't want to upgrade to the DS.

I think the "Wii2" (which it will NOT be, in ANY way, a "new Wii", by the way. It'll introduce yet another unique aspect into the mainstream gaming world) will be like that - Nintendo will release it and specifically state that it's NOT a successor to the Wii - but in all actuality, it will end up serving as one. It's just to make the transition between generations smoother and less abrupt, allowing adoption of the new console easier to carry out, especially if it does something funky, like the DS did.

I agree it will be very different, but it won't be out ibefore 2013, unless another company threatens to release a system which could cut the Wii market, Nitnedo would much rather spend their time making profits and refining their next innovation

I agree with the following predictions:
Market leaders this generation
Wii - Too big, too long to be a fad. Hasn't met demand yet, much less needed a price drop to move its produce.
PS3 - Will come in second. A bit dazed that it lost its leadership, but happy that Bluray is established and raking in the coin.
X360 - Third. But apparently happy that it probably will be profitable.

Out with the next generation.
MS first again. Tho considering the knock that RROD hit them with, the quality should be better. Some what cheaper, learning from the Wii example.
Wii second. But I agree that the Wii itself could gone on for a bit, like GBA did with DS, and PS2 is doing for the PS3. The point is you don't scrap a winner when it is still bringing in the money.
Sony third. I wonder what they will have learned from the Wii's success?

One area not mentioned in any prediction here is a very good size market that isn't being tapped yet. Namely, India and China. The first company that can successfully break into the upper middle class, who have the money for these 'toys', will add a lot of customers.

 You say you don't scrap a winner but then you say Wii will be out second, sorry does not compute, if anything the Wii winning will lead Nintendo to be the last out next gen

 GBA and DS Phat were winners too.  But both got replaced before Sony could get a stranglehold on the handheld market.  Yet neither were scrapped, until they no longer sold (with GBA still hanging in there).  

If some system is eventually going to replace your system, which some system eventually will, you want to make damn sure it is *your* next gen system that replaces it.  Of course, you want to do a slightly better job than what Sony's PS3 is doing to replace the PS2.  It could be agrued, I suppose, that PS2 is not "willing" to be replaced.  But this year will see its sales slip even with a price cut. 

wii lasting 10 years would still mean wii2 in 6 years...just like ps2 is still going even tho we have ps3

 and he means fitness freaks as in the ones who buy abcizers and thighmasters, not the ones who go to the gym or actually consistently work out

there is a HUGE market for those 'casual fitness items'

#2 doesn't compute

 either ps3 will do well and sell 80mil in 5-6 years or it won't get to 80mil...because if it can't sell well enough to do that, then it won't have a 'very long lifespan'...consoles not selling that well don't have very long lifespans

 after 5 years, if wii is at 120-150+ and ps3 is at 50-70, then sony will need to come out with a new console with full motion controls to be able to compete....they won't just keep ps3 around forever when it's not selling great