Gamercenteronline begged and pleaded and got its hands on three screens for Halo Wars, the real-time strategy prequel still under a TBA release date for this year. One looks like a close crop of a Sparrowhawk that we've done before. Not sure what exactly is going on in the other two.
Loitering around the site I also found what they touted as a new Mafia II screenshot. You can catch everything after the jump
The Mafia II screenshot is said to be set in DeLuca's Restaurant, even though this is clearly a warehouse shot. Not sure if that's a level title or not. But that's Vito, and it looks like he's about to waste a competitor.
And here are the other two Halo Wars shots.