Four existing titles for PS3 and PS Vita are coming to PS4, complete with cross-buy. That means if you already own Escape Plan, Flow, Flower, or Sound Shapes, they'll be ready to play at launch or soon after on Sony's next-gen system for no extra cost, according to the PlayStation Blog.
Thatgamecompany's Flower will be available on Nov. 15, along with musical platformer Sound Shapes. Flow and Escape Plan will join them on Nov. 29 after the latter is reworked for DualShock 4 controls--note that it still won't appear on PS3, likely for the system's lack of touch support.
Although PS4 is only backwards compatible in the sense that it may one day stream a large portion of the PlayStation catalogue, this move bodes well for the continued existence of its ample indie library.