"Along with momentum is technical mastery. There are more moves to pull off than the controls appear to have. Learning these skill moves isn't essential to the main story, but is vital to earning the best speed run or time trial. Learn 'em and love 'em. To give a brief example of what I am talking about, there is a certain time trial called "Playground 2" that at one point has you running up a wall, vaulting over a barbed wire fence, coiling your legs so you don't hit the barbs, rolling onto a group of steel beams, and hopping out of the roll across a gap onto another building. To clarify, this is the second area in the time trials section.
At the end of the day, Mirror's Edge won't be for everyone. It is really unconventional and innovative to the point that it may turn some people off altogether. If you are a fan of platformers, or even racing games, I guarantee that you have never played anything like this before. Mirror's Edge is fun, it's exhilarating, it's gratifying and it is definitely worth owning."