As detailed by PlayStation Network Operations Director Eric Lempel on the PS Blog, PSP Firmware Update 5.02 is now available for download below.
Download: PSP Firmware Update 5.02 (US) / PSP Firmware Update 5.02 (EU)
To quote: Just a quick update, we'll be making PSP firmware update 5.02 available shortly.
This update improves system software stability during use of some features, including the PlayStation Store. More PlayStation 3 News...
I do not see why sony comes out with so many updates, there is no need for them. They should maybe come out with one every 6 months, its good to show that they are caring about the customer but it shows how imperfect their system is.