Already been done, could be done with the same decrypter as 3.10 :P
Taken from maxconsole:
For those of you that wish to decrypt the new Sony firmware here is your chance to.
Team C+D latest decrypter works with 3.11.
To dump the firmware open up the Eboot with psp brew or PBP unpacker
2.Extract the DATA.PSAR to the root of your memory stick.
3. Copy psar_dump2 and psar_dump2% to your GAME150 folder. (Or whatever you kernel is set to)
4. Launch it from the game menu.
5. Select what option you wish to have. Then it will dump the contents to the root of your memory stick.
This was the same decrypter they released to to decrypt 3.10 it also works with 3.11 so this is not a new release of the program.
Thanks Team C+D for your great work. Sonys new firmware defeated again.