I have referred to this a bit in other threads, but I didn't want to create one because I'd probably be called a fanboy for it.
Konami really screwed this game up, especially on the PS3. Many people are actually returning this game, and rightfully so. There's no excuse for launching a barely working game on consoles, where you (as a developer) have the benefit of being able to easily test your game on the target hardware...
My Mario Kart Wii friend code: 2707-1866-0957