Should reach 50% by the end of the year. Then hopefully third parties realize that the Wii is, in fact, the market leader and will adjust accordingly.
This will happen to some extent, but I do believe that the HD systems (PC-PS2-360) are still very viable as a separate userbase if the companies involved can exploit that audience. I definitely don't believe we'll see a repeat of PlayStation2 style market consolidation.
It's funny that third parties suddenly care what's "viable" when last generation they mostly cut support for consoles once they discovered that weren't selling well (GC, Xbox never got much in the way of exclusives.) But anyway, you're already seeing this happen in Japan. PS3 game announcements are drying up, and 360 games do very poorly there and most from Japan do poorly here, too. Third parties have reached the point where developing for the HD consoles doesn't outweigh the potential of a hit Wii game in their repertoire, and the highest selling Wii games, aside from Wii Play, are the games with the most effort put into them. So those resources are needed to please the much larger Wii market, and cannot be solely allocated to two consoles that will constitute less than half the total market. The habit of giving the 360 and PS3 more resources simply because they require more will be over.
I mean think about it. Say you're Capcom, and you just got a telegram from the future. The Wii is the #1 console in every market, by a large margin. Would you then focus on making 2 or 3 360/PS3 games when you could make 6 or 7 Wii games with equivalent effort (both into game quality and manpower) and time? Resident Evil 5 is just hogging all the developers and resources, your profits are falling and the most exciting thing you've made in 3 years is a 2-D game with NES graphics that sold the best on Wii. Would you sincerely think more 360 games is the answer?
Say you are Konami. You put all your eggs into this one Metal Gear Basket, it comes out, and sells less than the previous game and fails to excite the PS3 consumers much. The game cost SIGNIFICANTLY more than the previous, which was a PS2 game of all things. Would you then greenlight another gigantic, expensive, PS3 exclusive, especially if you couldn't use the fading brand of Metal Gear again so soon?
Say you are Square Enix. Your biggest game that you've announced is Final Fantasy 13, a game with a release date at some day at some point in the future, sometime. Your actual biggest game this gen, based on unit sales is Dragon Quest Swords, a game that sold 710,000 worldwide and was even developed FOR you by a Nintendo second party. Everything else is a flop because Japan doesn't buy 360's and American 360 owners don't buy RPGs from non-American companies. You are funding your albatross of a Main Series Final Fantasy game with DS sales that you've even had to jack up $10 over the standard. If you knew then what you know now, would you have seriously put Final Fantasy 13 on the last place, loser console this generation when you could have put it on the market leader and actually have released it by now?
These questions are being asked every single day at these companies, and if they aren't, then they deserve to get replaced by the rising third parties like Marvelous that see the Wii as an opportunity rather than a dumping ground to scrape funding for unsustainable products, no matter what magazine scores they get.
EDIT: Lindy, that guy's opinion kinda sucks, because he's using the tired meme of "The Wii will stop selling at some point," and "Wii's days are numbered." Which is the sort of thing Gamefaqs GC fanboy said of the PS2 in 2002. And the sales totally refute this but if that's what the Bethesda guy wants to believe, he can.