I released an update for CheckRegion that identifies new Wii models (gc-less). I also added a few new functions, if you are interested. Each function is documented, and there is a sample app.
http://www.hacksden.com/showthread.php/3743-CheckRegion-Detect-any-Wii-s-original-region
I created a patch that incorporates the new serial numbers, which I've attached. I haven't tested it, but it should work fine. None of the new functions are added.
Note that there is no longer a need for a custom conf.h file, as I made it a separate library.