So how is HDMI 1.4 output possible on older consoles? It turns out that the new standard is rather conservative. A 1280x1470 framebuffer actually requires less bandwidth than native 1080p - and both Xbox 360 and PlayStation 3 have supported that for ages. Even 3D Blu-Ray movies only run at with the equivalent bandwidth of 1080p at 48 frames per second - well below the 1920x1200/60Hz max of the interface. So HDMI 1.4 support on an HDMI 1.2 console boils down to making the hardware output a custom resolution and nothing more.

In terms of Arkham City itself, the game uses the same TriOviz technology as Gears of War 3 - though the Epic title was restricted to the half-res side-by-side functionality we've seen on other 360 stereo 3D games. Curiously though, while both games seem to be operating at native 720p on both platforms - as we would expect - the Xbox 360 version seems to have a one pixel wide blur across the whole image.

From EuroGamer