Yeah, thanks for that. I've looked into a bit more and it seems there is a fairly substantial home brew scene out there. Actually, after looking into it, the ScummVM for Wii could be purely awesome.
As for the Nintendo lockout, it seems that you can soft mod or hard mod your system. Soft modding is obviously far cheaper, but risker in that you can easily brick it and Nintendo can delete the soft mod with updates (which I'm assuming is what they're talking about). Hard modding, it seems avoids this. Nintendo can still delete your "homebrew channel" with an update, but all you have to do is pop the disk back in and reinstall. Nothing on your system (firmware wise) is actually changed, so they can't lock that shit out...it's just that the drive is emulated somehow and that allows you to run anything on it...or something like that.
I'm still looking into it, and although it doesn't seem like a way to build a media center, it seems like it'd be pretty fun to mess around with some stuff. I mean hell, if I'm going to buy a gamecube anyways, might as well buy a Wii.