Hedgehog at Xbox365 has posted a Hands-On article about Unreal Championship impressions from the Xbox Live Boot Camp event, and compared it to Halo:

So hereТs the million selling question ladies and gentle gamers. Is Unreal Championship a better multiplayer experience than Halo? To put it simply yes! Unreal Championship is just one sick head-trip of a shooter, which is going to have Xbox Live users screaming for more, once they unlearn Halo of course.

He goes on to cite that while the controls are very similar, character movement is so much higher that Halo players may have difficulty adjusting.