Er, I always thought Melee Yoshi's Island was "Super Mario World stage". Same overworld look and music. ...oh, duh, the first world in Super Mario World was Yoshi's Island. Darn it, there have been too many Yoshi's Islands throughout the series. So in Brawl, we have SMW1 Island, SMW2 Island... and Melee had Yoshi's Story Island, which I hope never makes a return (stage was too small).
Cool, Onett's back! Seems they're really holding onto the EarthBound references. I don't think there's any stronger references to EB than in the Smash Bros. series. You'd think Nintendo would release the actual games, then. We did eventually see some Fire Emblem games after all.
Still waiting for Brinstar Depths (it's Norfair, gosh darn it! Norfair's below Brinstar, entrance to Norfair is close to where Kraid is, and you're using the Norfair music! Get it right!). Not my favorite stage to battle on, but it had Kraid and wonderful music.