I'm sad that Mewtwo and Roy didn't make it into Smash Bros. Brawl, but there's a certain comforting circularity about the original twelve Smash Bros. being in all three games.

That being said, there's also a comforting circularity about Jigglypuff retaining her status as the Unlikely Badass in all three games. From what I've heard, she might be even tougher in Brawl despite her Rest being less powerful.