As expected, the first Modern Warfare 3 gameplay trailer is to air In the US this evening.
Infinity Ward creative strategist Robert Bowling confirmed the exact timing via Twitter, saying: "Modern Warfare 3 world premiere gameplay trailer tonight on NBA Western Conference Finals around 6pm PT (2 am UK). I'll link HD here."
So you'll be watching it last thing tonight or first thing tomorrow, depending on when you hit the sack.
Bowling also said this week that the MW3 game engine features plenty of improvements over MW2's.