http://www.jeuxvideo.com/reportages-videos-jeux/0000/00000273/trackmania-wii-premiers-pas.htm
tl;dr translation : Trackmania wii is in developpment, Q1 2010.
Features : multiple environment (desert coast stadium rally island snow), Level editor w/ online exchange, local/online muliplayer, 4 player split screen local muliplayer, online mode (turn after turn ://), multiple controls (wiimote - mariokart style wheel, w+nunchuck, pad)
Yay ! turn by turn online is a bit disappointing, somehow they say there's lots of contents.
w8&c