Pit is by far one of the best characters in the game at this early stage of Brawl's metagame.
He has:
1) The best recovery in the game, bar none.
2) One of, if not the best, ability to combo people. Even if properly DI'd out of, a big character will get ~15-20% damage for his spinning sword attacks, including uair, fair, side-b, etc.
3) He has the best projectile in the game so far as I've seen, and his ridiculous air time allows him to spam it. The matches I play against him, he forces me to approach because he eats my shield with arrow spam then can just combo me with his ridiculously fast start-up and end-lag times.
4) He actually has kill moves. Why mention this? Metaknight, in my opinion, has less combo ability than Pit (some would disagree), but has no kill moves whatsoever aside from edgeguarding. Pit has bair and dair over 100%, and that's not really unreal damage considering I've seen him rack up that much in ~15 seconds or less.
The only counter to this is that he's light. This still doesn't matter. Unlike most characters, Pit really can't die at low percentages because you can't edgeguard him well enough with his recovery, which means he HAS to die by being straight-up KOd off the screen. Bowser's heavy as ****, but he's got a ****ty recovery which allows people to edgeguard easily at low percentages. Heaviness isn't everything, and I've found that you need to get Pit over at least 90% to kill him (as Dedede, a character who, among other things, should kill at lower percentages). It's hard to even get him there because of his speed, ridiculous priority, and combo ability.
Essentially, Pit will be top-tier unless something drastically changes. Maybe not THE best character, but he will be up there.
And please don't say he's really hard to play as I've seen. Sure, I bet he's hard to master (like every other character...) but his learning curve isn't steep at all. The very first time I played Pit (without knowing his moves) I destroyed a Wolf player who had beaten me before with my main.