The system is about the same size as I expected from pictures, and the built-in handle should be useful for taking it to a friend's place or something. I only got Luigi's Mansion, but it's fun so far. The graphics aren't quite as impressive as I was hoping, but it's at least PS2 level. The save file takes up about half the memory card 59, though. Nintendo should consider releasing larger ones. And would it be too much to ask for a wireless controller? I want to play from the far couch.
Overall, it's decent so far. I think Nintendo finally has another winner.
Edit: Whoa, try holding down Z when the system boots! :O