Looks like Harmonix let this slip under the radar. Unofficially announced, I bring you Frank Turner's "I Still Believe" - for free!
At the moment, it's for the Xbox 360 and can only be purchased from the console itself - if no payment option is attached. No idea for the PS3.
Download size is 19.20MB and requires Rock Band 3 or Rock Band Blitz to play (of course, you knew that already).
Well, brace yourself for Rock Band 4… coming later this year on the PS4 and XBOX One.
And yes, all DLC purchased on the PS3 will be avail. in the PS4 game. Likewise all 360 DLC purchases will be available in the XBOX One game.
As for this free song, it is meant to be available on the PS3 as well, but only in the US. For now, all PS3 users in AU/NZ/EU/UK are still waiting to get our hands on the other 5 new songs released this year for Rock Band 3.
How long has it been since the music games genre stop being the in thing already?