There are still worthwhile games coming on the Wii next year, and I'm sure a lot are unannounced games. I think the problem is if the Wii is your only system. Gamecube got by because it still had third party support since it was in the same league as the Xbox and PS2. Wii only has those middling third party games and the Nintendo games, it's even made worse since a good deal of those Nintendo games are now things like Wii Music, Wii Fit, and Animal Crossing.
I'm not so sure.
The Wii has really yet to prove that it is anything other than a shovelware dumping ground. Once the PS2 fades away, the PS2 port ups will no longer exist but at that point, the next round of Ubi Petz will be out and sell 500,000 copies, alongside Wii Kitchen, and Wii Love The Zoo to be the biggest selling titles of the year for the Wii.
Unless Nintendo breaks their habit of one iteration of Mario, Mario Kart, and Smash Brothers. If Galaxy 2 were coming to Wii, I might look into getting another Wii again. Might. If the future of the Wii is now Animal Crossing and Wii Music, I owned the Wii for the brief moment it was worth owning. Galaxy was a great game and Mario Kart was not that bad (despite the extremely cheap AI in the latter cup races). Brawl would have been ok if the game's pacing wasn't so slow and the online worked once in a while.