Wii titles are most likely to be playable on consoles worldwide, Nintendo's own included.
Games writer, friend to PGC and heavy drinker Chris Kohler is reporting on his Wired Games Blog that the Wii console, like the Nintendo DS, will be able to play games from any region of the world.
The report implies that region protection can still be put in place by publishers if they so desire, but Nintendo's own games won't be locked to a specific country.
Kohler's blog also has two other pieces of Wii info. First, downloaded Virtual Console games are tied to a central account, and can be re-downloaded if they are lost. Second, the USB ports on the Wii console can not be used for storage expansion, at least intially. All storage will be via the onboard 512MB of flash memory and the SD card expansion slot.