It is surprising that the support for the Nintendo Wii is currently so poor in comparison to the XBOX 360 and even the high-priced PlayStation 3. All that can be hoped is that the Wii titles are of a higher quality, rather than rushed updates of old XBOX/PS2 titles...
To be fair. Sega put a lot of support into the Cube and it didn't pay off as much as they'd hoped. Sonic Adventure 1, adventure 2, Mega collection, Gems collection, Heroes and Riders. The first 2 having the GBA link up feature. Exclusives like Billy Hatcher (under rated imo) and that moster creating game - monster island (?). Plus crazy Taxi and a few others. Yeah some of them may be ports, but they we're released. On top of that. Some of the Sonic games we're timed exclusives and didn't appear on the PS2/Xb for a good long time, which they should've done early on.
I still think theres a lot of support for Nintendo from Sega. If they create 7 Wii exclusives and busily port games between PS2 and PSP, i'd be happy with the exclusives. Also, they may see that Nintendo is moving for a different audience and want to create new games, not franchised sonic games, for the Wii.