Since nobody started a thread yet on this, we will use this one for it! CJPC installed it, but didn't try dumping yet to see if it still allows it OK or not... awaiting the official changelog as well!
The PLAYSTATION®3 system software version 1.31 update includes the following:
Settings
You can now register the BD remote control in [Register Bluetooth® Device] under [Accessory Settings].
[BD/DVD Video Output Format (HDMI)] has been added as an option under [BD/DVD Settings].
[Backup Utility] has been added as a feature under [System Settings].
You can now select the hard disk format method in [Format Utility] and [Restore PS3™ System] under [System Settings].
The method of selecting output resolution has been changed in [Video Output Settings] under [Display Settings].
Game
New for 1.31: You can now play PlayStation®2 format software titles that must be installed on the hard disk.
Other
The compatibility of USB devices with PlayStation®2 format software titles has changed. For details on USB devices that can be used with system software version 1.30, select here.
New for 1.31: Playability status with the PS3™ system has changed for some PlayStation® and PlayStation®2 format titles. To check on the latest status, visit the search site for compatible titles.
You can now access the XMB while pics, movies, music are being played. Or was this feature released in previous updates? I just happened to notice it after my update.
I hope Sony make an update that will stop the inserted disc from starting up automatically when powered on. That would be on my most wanted firmware feature.