Just my opinion, of course, but the problem I had with this game was that its premise was a COMPLETE LIE.
This was meant to be a game based on 'free-running', yet every level had perfectly to-the-very-footstep preconceived paths throughout every level, meaning you constantly had to stop to see where the next objective was. Way to break the flow of a free running experience! If anything Mirror's Edge is a memory puzzle with occasional gunfire.
There was no spontaneity in the movement throughout the levels at all. If you had the objective of "get from point A to point B" and you could use all your skills in the best way you could to find your own way to achieve that goal, then that would have been a true 'free-running' game. But no, you deviate from the pre-set path and you fall to your death. If it were a puzzle game, that would make sense, but when you have guys with machine guns running after you, stopping to look for the next glowy object to grab onto makes for a very stop-start-stop-start infuriatingly fragmented experience.
I appreciate the idea, and it was the hope of more open gameplay that compelled me to take it to the very end. In retrospect, however, I hated it completely.