I have plenty to complain about with the game's content.
1) Falco remained in over a more original moveset (Krystal w/ staff) and over a deleted original moveset (Mewtwo). Not cool. I save judgement on Wolf because he actually seems to move and act a lot different. The landmaster is a joke, though.
2) The SSE. It seems almost a shame so much time and effort was invested in this Kirby-knockoff beat-em-up. Poor enemy/boss selection (Mother and Metroid bosses, but only Mario regular enemies besides original ones?) It might be slightly fun, but it will not endure. After everyone has 100%ed it, it will be over and done with, and abandoned, while the multiplayer lives on. Miyamoto was perhaps right when he advised Sakurai not to focus on Single Player.
3) Masterpieces. This almost infuriates me. Whatever space was wasted putting in demos of ancient Nintendo games (conveniently buyable on the shop channel!) would have served better as anything, even a single trophy or sticker. I thought Nintendo was above this sort of thing.
4) Tripping. Almost enough said there. Why should you be randomly punished just from moving around? The point of the game is to see how well you can control your character. Yet in this game, control will be randomly wrestled from you for no reason at all.
5) Lack of online options. You know, in a lot of games, you can CHOOSE whether to rate or unrate games. Or you could choose whether to see anonymous names or not. What's the use of parental controls? What's the use of the RATING (teen, not for easily corruptible kids!)? Nintendo has shoehorned us into yet another watered down online experience. Not to say I won't enjoy it, though.
6) Target Test was dumbed down. Not only do the generic levels not uniquely test your characters ability, but three of the five involve manipulation of items, which is even FURTHER removed from your character's ability.
I think that's about it at the moment. In no way is Brawl perfect. Mid to high nine at the most, but not a 10/10.