http://pc.ign.com/articles/717/717236p1.html
Then you fucking MA or snipe them out of the air damnit!
During this process, we began to address the problem of boarding the enemy Titan. One obvious solution was giving each soldier a jet pack. This would certainly solve the boarding issue, but we felt it would harm the solid infantry versus infantry combat we wanted. For example: imagine a fire fight where those on the losing end could just decide to zip off into the sky when they felt things were going badly. We wanted a solution that would keep soldiers on the ground, fighting each other from street to street.
Then you fucking MA or snipe them out of the air damnit!