Footage and screens surrounding MMO MechWarrior Online have to date featured open maps, but today's trailer shows there will be at least a little variety in the final game. Featuring urban map River City, it offers a full three minutes or so of gameplay.
What really stands out to me here is Piranha Games seems to have nailed the tension critical to a good shooter of any sort: when you see one mech creeping up on another or they both eye each other at the same time from a distance, you're likely to tense up in anticipation.
River City reveal - YouTube
MechWarrior Online launches sometime this year. It's currently in beta; hit the source to sign up for it.