Halo Wars
Halo Wars, obviously, is going to be huge. Apparently, the folks at Ensemble have been sitting on this deal for about a year, and the developers and designers working on the game have been grouped together under the code name "Phoenix." But Ensemble isn't really ready to talk about the game beyond what they've shown on the official site. Sorry! I did see an imposing , life-size Master Chief statue in the office, though.

The WarChiefs
This expansion pack for Age of Empires III ships on October 17, and it's looking really cool. And it's practically a standalone game, although of course you will need to have AoE3 to play it. You'll be able to play as one of three new Native American tribes, or play as one of the European powers from the original AoE3. If you do play as one of the Euro countries, you'll get new features such as the "revolution." Basically, if you need a last-minute troop surge to finish off your foe or are scrambling for a few more fighters to stave off annihilation, you can revolt against your home country and transform your peasants into soldiers. But you don't get any more peasants for the rest of the battle. So it's an all-or-nothing gamble.

The Secret Project
Ensemble has one more game up its sleeves that it isn't talking about, and barely even admitted that it exists. Not sure what it is, but it's interesting that Ensemble has grown enough that it can make several games at a time, rather than just cranking out one title every three years or so.