Game choices are:
Alien vs Predator
Just Cause 2
Company of Heroes GOLD
Jet Set Radio
Kane & Lynch 2: Dog Days
Serious Sam HD: The First Encounter – Currently less than $5 at GamersGate.
All of the games listed above use Steamworks.
In my opnion, the best deal would be CoH + Jet Set Radio. At least for NA residents. The other games can usually be purchased for less than $5. If you want to play now it’s not a bad deal though. Also if you purchase CoH + any other game you should come out ahead. I think the cheapest that game has been was $7.49 or so.