GEN-B has been released with a bunch of bug fixes. For those of you who don't know, GEN is currently the only firmware that can bypass the security check from the Sony PSN. Theres also a new feature available. Remember that anti-cfw game that was released in Japan? GEN-B now has the ability to play that game.
Heres the official changelog:
* Bug fix: the VSH menu can now be disabled
* Pressing Select can start the recovery, bring up the VSH recovery menu, or do nothing at all (for those who wish to use Remote Play between their PSP and PS3)
* Update via Network (taken from M33)
* * That Evangelion Jo game we told you about; it can be launched & played now
* Pandora (converting the battery to/from the Pandora-state) and Shutdown Device options added to the VSH menu
* Flash1 format option adds a check that prevents a flash1 format if enabled
* Access [remains open] to the PlayStation Store and Remote Play continues working
What you need:
•A PSP-1000 or PSP-2000 v1 or v2 already running Custom Firmware 5.50 GEN-A. DO NOT attempt to install this on a PSP-3000 or any PSP with a TA-088v3 motherboard.
5.50 GEN-B:
http://www.psp-hacks.com/file/17645.50 GEN-A:
http://www.psp-hacks.com/file/1745