The testers tested 41 games, and they all worked. 4 , however needed a firmware update to run, but once they did a double boot they worked fine. They didn't specify which games these were, but I can probably guess they were
Mario Galaxy
MP3
Twilight Princess
Super Paper Mario, or possibly SSBB.
The SSBB copy they tested was the JP version. So it sounds like it does eventually work, but I'm not sure if you'll need to perform the update for it to work, or if the double boot will be enough to simply bypass the update.
I feel like we're going round in circles xP
Well, I'm pretty sure It'll work now. Now all I have to worry about is when the Freeloader will come, and if my disc lens is clogged with dust, and the copy of Brawl won't work ><
I got my Wii at Christmas though, so it shouldn't be too bad.