It's been confirmed in the Bethseda Skyrim blog that the Skyim DLCs; Dragonborn, Hearthfire and Dawnguard will be available for PS3 this February. Unfortunately it doesn't say when in February, but the good news is that the DLC will be at 50% off during their launch week!
The Dragonborn DLC will be available on Steam on the 5th February for PC in English, French, Italian, Spanish and German.