During Sony's E3 conference Mark Rein confirmed that Unreal Tournament 3 on the Playstation 3 will run Unreal Tournament 3 PC mods. This effectively providing the first ever case of true cross platform compatibility between PCs and consoles.
Mark Rein put it quite clearly that "You'll also be able to share mods between the PC and PS3 platforms". He has also said that the open source platform Sony is using makes this possible. This may make it very unlikely the Xbox 360 will have such cross compatibility.
