I agree with insanolord I think Sega would be a good choice. They're not shy about about releasing "core" games on Wii and could heavily promote it.
Nintendo publishing it would restore some confidence in them on my part after E3 though.
I hope the fact that Nintendo are showcasing it means that its actually quite good. If the Conduit doesn't turn out fantastic there will be most likely be a slump in my Wii playtime.