Sony released PS4 firmware 5.55 yesterday.
The official changelog states that “this system software update improves system performance.”. This could be anything, including patches for undisclosed exploits on the console. As always, if you intend to hack your console, we advise not to update unless you really have to. Better yet, if you can afford it, the easiest way to get the best of both worlds is to have two PS4s: one for gaming, another one for hacking.