Other way around - you can play online, but the Wii version will more than likely, never have downloadable content.Originally Posted by GC8
"And that's exactly the mentality of Guitar Hero III: Legends of Rock for Wii. It isn't broken, so why fix it? Rather than throwing meaningless motion control into the mix, or trying to "Wii-ify" the design by replacing the core five-button guitar with some alternate way to play, Guitar Hero III is exactly how it is on other consoles; pure, traditional entertainment."
"Guitar Hero - as we've stated numerous times already - doesn't need a change from its original design, so the Wii version does very little to screw with the formula. You'll have the same overall guitar design, you'll still have online play, you'll get the unlockable tracks, characters, outfits, and guitars, and you'll still be able to rock out in co-operative or competitive modes. The only thing missing in Guitar Hero III for Wii is the downloadable content, and while that's a huge must-have for veterans of the series, a veteran most-likely also has access to the other versions anyways, and can get their enjoyment elsewhere if need be. For everyone else, Guitar Hero III is still going to be a killer package on Wii."
GHIII Wii Article (Oct. 15)