Wrong my friend, the PS2 was HD-enabled too :)
Gran Turismo 4 had a 1080i mode, and if the PS2 could pull 1080i with a 4MB framebuffer, the Wii should be able to pull out 720p with a (rumored) 3MB one with double buffering.
Just consider that the bandwidth of the Wii's eDRAM is unknown :P







