I've been playing brawl ever since it came out. When it first came out I played it like any regular casual would, and I thought it was amazing. I had never played a smash game before, but I realized that the game I picked up was a game that I could play for hours and hours. I also loved the various of characters they added into the game.(I picked up the Pokemon Trainer first) I would have never thought to see Sonic and Mario duke it out besides in the Olympic Games. The Subspace Emissary was a nice touch as well, even though back then I never completed it.
I also like the various of things you can do in brawl (Ex: IC's Chain Grabs, Dedede infinities.) Though they might seem annoying in one's eyes I find them quite fun to pull off.
And the various music tracks in every stage was a big plus. Sometimes hearing the same song over and over again can be pretty annoying...
I have played Melee for the first time a few weeks ago, and I really can't get used to it for a lot of different reasons, but lets just say you need a lot of skill to play Melee and PM. A lot of skill that I don't happen to have.
The only thing I don't like about Brawl is the realistic look to it. I loved the cartoony look to Melee. Oh, and I dislike the colored hue in Ness and Lucas's eyes. Seriously I never understood why those are there.