Team GENyUS has released CFW 5.50 GEN-D!
They are also trying to port the MS Speed Up option that was in 5.00 M33-6 into their next CFW release.
[Source - PSPGen]
I uploaded the Update without the 550.PBP file so people who already have that file in their PSP, can download the file much quicker.
For those who do not have the 550.PBP, I uploaded a seperate file for you just incase.
XGEN Update & Pandora v4 CFW 5.50 GEN-D
5.50 OFW Update