- Both Wii and GC discs are the same type that deviates slightly from the standard DVD format. As long as the Wii U drive can physically load a GC disc in an adapter, I'm not aware of any technical limitation that could prevent the drive from reading GC discs just as effortlessly as it reads Wii discs.
The vWii firmware probably won't acknowledge GC discs in adapters until a friendly programmer convinces that firmware to branch out a bit. For now, I'm just happy being very optimistic that GC disc support will eventually be a reality on Wii U.