I welcome the cross-platform approach, but I seriously doubt that by fiddling with numbers ("handicaps") the devs can create a level playing field.
For starters, it is not level simply by virtue of handicapping.
Second, even games traditionally "balanced" for different controllers are not really balanced at all, even on the same system.
Take a driving game, and pit two players against each other, one with steering wheel and another with an analog gamepad. I can guarantee that one will have a slight advantage over another. The game may slightly skew the controls towards gamepad or steering wheel, but it is not balanced by a long shot.
My brother-in-law has the exact same steering wheel and gamepad I do, and when I use the gamepad and he the steering wheel, I tend to win on curvy tracks but lose in ovals (analog gamepad is too sensitive to steering and you lose too much speed); when I take the steering wheel and he the gamepad, I consistently lose on curvy tracks but always win in ovals.
Again, I applaud the developer's efforts, but a balanced playing field UT3 will not be. Those that think PC gamers have the inherent controller advantage may have a rude awakening if Epic tinkers with the control balancing - it just might be "too" balanced in the gamepad's favor.