Games! Or, I should say, games. Mostly older games, but games nonetheless. CES isn't the place for four year-old tech like the PlayStation 3 and Xbox 360. But that doesn't mean they're totally absent.
Killzone 2, for example, is playable in Sony's big booth, as is Resistance: Retribution. Microsoft brought pre-release builds of Warhammer 40,000: Dawn of War II and Halo Wars. While much of what Sony has in its booth shows off fancier tech - like PSP and PS3 connectivity and a massive stereo system - Microsoft seems more content to just give Lips and Banjo Kazooie floor presence.
The full list of games brought to CES by the big boys - there are plenty of booths with Rock Band and Guitar Hero set ups scattered about - is after this. We're off to go play some of this stuff!