Upcoming Amazon PC DD Deal
Right now all of these are Steam keys (individual keys when you buy the bundle just like the last one) except for Stalker and Guerrilla. There is a high chance we'll get those as Steam keys.
S.T.A.L.K.E.R.: Shadow of Chernobyl
Red Faction Guerrilla
Red Faction Armageddon
"I'm still not locking down a date but it'll likely happen sometime next week."
Source: Amazon DVG rep