I hadn't bothered to pre-order at Gamestop and when I called them it sounded like there wasn't a very good chance they'd have any for non pre-ordering customers (because Gamestop is lame) so my friends and I popped over to Wal-mart around 11:30 and waited around, grabbed the game, and then came home and played for about 4 hours.
Close to 30% through Subspace Emissary. I've been kind of surprised how different the game feels than Melee, but it's just going to take some getting used to.
My initial pleasant surprises so far: Lucas and especially Ike are way more fun than I anticipated. I didn't like Meta-Knight all that much.