I think it is safe to say that a lot of players expected to be doing flips and running on roof tops while they fighting and what not.
Like in this misleading trailer: http://www.youtube.com/watch?v=s-kVnw4RA80
We got none of that type of action in the game. Now before you say that it was just a cinematic trailer and doesn't represent the game what so ever, let me just say this: The cinematic trailer is often the first impression people get of the game.
My impression of the game was that story was not a main factor in the game, nor was team play. There was nothing to suggest teamwork at all in the trailer. It actually had to watch the trailer again to realize there were even two sides. Many franchises usually have their trailers introduce characters or set up the plot of the story. Brink had none of this and the fact that their was no dialogue made more evident the story wouldn't be a main focus for the developers. What I took away from the trailer was that parkour would be a major part of the game. It isn't.
You want to know why it isn't? It is because of Body types. Limiting the amount of parkour a character could do by body type is completely holding back the game and the SMART system. I was expecting interesting map designs that would use SMART to its fullest. Instead we got linear Maps completely centered around objectives so that Heavies could actually contribute to the team instead of sitting on the ground doing nothing. In order to balance the maps for the three body types, the influence that SMART would have on map design was dramatically reduced. Its not like the developers completely forgot about SMART because there are still a few places that only lights can get to but there is no combat with people sprinting and shooting off rooftops or any of that amazing stuff hinted at during the cinematic. The map designs are boring because the maps focus on the objective too much at expense of SMART.
I do realize that this game is a team based shooter, but still Splash Damage could have made things a bit more entertaining than gathering in a mob to accomplish objectives. There is nothing wrong with liking the game the way it is, but I do think that my disappointment in SMART is shared by other members of the community. I hope that Splash Damage will learn from their experiences from Brink. And who knows maybe Brink 2 will be the game to truly revolutionize the FPS genre.