So you missed the parts with destructible environments, crawling, and possible low-gravity stages? Not to mention the new Smash Bros symbol that enables Super Moves?
There was destructable environments in SSBM. Brinstar and Ness's stage to an extent were destructable. Final Destination was low-grav when you fought Master Hand, for that matter.
Crawling, though, I did miss. Can't really think of how it would work all that well in 3D (unless there's going to be split-screen).
Super moves, blah. Seen it in Power Stone.