#2: Braid, Cortex Command, Machinarium, Osmos, Revenge of the Titans
#1: World of Goo, Aquaria, Gish, Lugaru HD, Penumbra Overture, Samorost 2
Steam codes are currently available for the first 150,000 or so people. Samorost 2 is on Steam but it isn't included. Cortex Command and Revenge of the Titans are not on Steam yet. When they are, they'll be automatically added to those who typed in their code.
The bundle ends in a few more days.