Obviously it was a lazy port.

Ya im kidding...

I think poorly executed is obviously the culprit. There is absolutely zero polish to this game. In theory the gameplay should be fast, smooth and responsive, to really take advantage of the parkour elements. But it is slow and clunky. If you play it, you get used to how it controls and there is fun to be had, but the gameplay ultimately feels flat. The graphics are dated looking as well. I wasn't necessarily disappointed because I saw this at E3 2010, and it looked bad. 

It's kinda a slap in the face, but Splash Damage was one of the devs dismissed Uncharted 2 by saying that Brink would surpass it graphically and be the next evolution in gaming.

I rented this, played it for 1 hour and exchanged it.

Looked like crap, gunplay was crap, load time was terrible...next.

So much for a 'revolution' eh.