Sony released the Sony PSP 3.01 Firmware upgrade just days after the 3.0 release. The stated reason was to address a security vulnerability. I’ll guess this translates to the 3.0 was cracked by PSP enthusiasts who like to run their own apps on the PSP.
Many of the new 3.0.x features tied into the recently release Sony Playstation 3 game console. It also adds the ability to access online (via WiFi) manuals for both the PSP and PS3. Support for a Sony USB camera is also in this upgrade. But, the camera is not available in the US as far as I can tell.
The most surprising thing about the upgrade to me is how long the download took over its 802.11b WiFi connection. I didn’t time it with a stopwatch, but I believe it took well over an hour over a relatively fast broadband connection.