I would say that this has been a long time in coming – to see the DualShock 4 controller that comes along with the Sony PS4, play nice on the latest generation console’s predecessor, the Sony PS3, in a manner that does not require you to plug it in in any way. For those who have been using the arguably improved DualShock 4 controller to enjoy games on your PS3, it has been a tethered experience – and not a pleasant one when the distance that you have to sit away from the TV happens to be limited to the length of the controller’s cord. This is no longer the case, since Sony has recently enabled wireless support for the DualShock 4 controller thanks to the most recent PS3 firmware update.
Of course, in this particular update, it will remain as a generic controller without any kind of motion or vibration functions working, and the compatibility of this controller with some of the games are suspect, but at least you are no longer stuck to the limitations of a wired controller.
Reddit has the necessary instructions for you to pair up the DualShock 4 gamepad alongside your Sony PS3, and hopefully all of the kinks will be ironed out eventually – including the compatibility issue with certain games.