Unreal Tournament 3 is 30fps on both consoles with minimal screen tear. The 360 version has better motion blur effects, improved levels of detail in the maps, an extra bot and of course an exclusive split-screen mode. In my tests both versions showed 0.5% screen tear in the frame accurate clips I used. However, these clips were designed to be like-for-like. I've no idea how that figure alters on either platform in the heat of intense, engine-stressing gameplay - likely it will rise significantly (I could do non like-for-like tests but really screen tear is not an issue in this game).
You'd think it would be a good baseline test except that the coders had a lot more time with the 360 version and it shows from a technical perspective, even though both are beautiful games.
In terms of UE3 generally, games like Rainbow Six Vegas 1&2, Turning Point, Stranglehold and Army of Two show that the engine can produce basically like-for-like results with just AA missing on PS3.
However, other games show that UE3 hasn't been fully mastered by PS3 developers:
Blacksite Area 51 (abysmal frame rate on PS3)
Turok (lower frame rate, screen tear, but nicer ground textures on PS3)
Medal of Honor: Airborne (lower frame rate, no AA)
UT3 is a great showcase for what UE3 *can* do on PS3 though and it's easily the loveliest looking game using the engine on the platform.