I like it, but for some reason I kind of hope it isn't the final version of the opening - I liked Melee's opening much better. Though I wouldn't be surprised if there was another opening and it included several of the shots in this montage. Maybe the video's music timing is off or something.
I thought there were a couple redundant shots - two of MetaKnight right next to each other, and two of the Halberd in opposite directions at the end.
Maybe this isn't the final version of the opening? A leaked beta opening?