Rol, didn't you also say the Wii would easily beat the Xbox 360's NA sales, and have a counter for the past few months, taking it down when it was deemed vastly impossible?
No system has ever, ever, started out with a decent marketshare, and gone on to totally dominate the marketshare %, expect *maybe* the PS1, since it had the Saturn to compete with in the beginning.
Not only this, global marketshare for the Wii has been about 40-45% since the beginning of October. Yes, the Wii might have more supply next year, but why do you just assume the PS3 and X360 will roll over, and never have anything to compete next year? You do realize the Wii has a very weak Western lineup (from what I've seen) for 08, don't you? The X360/PS3 have Fallout, Army of Two, GTAIV, Silent Hill 5, RE5, and about 30 other mid-sized games that aren't coming out on the Wii, not to mention other exclusives (but the Wii games cancell that out).
So with huge multi-plat games like GTAIV, with the Wii having absolutely no comparible 3rd party game, why is the Wii going to suddenly increase it's marketshare? If games matter, then the Wii will see decreased marketshare vs. a more competitive field with reduced price X360s and PS3s next year vs. a Wii that's seen the bulk of it's cards on the table by mid-08 (atleast for the rest of the year).