PSPGen has cracked the encryption keys and decrypted EVERY file of the 6.00 firmware update!  Unfortunately (hopefully it is a flawed google translation)

Magixien Wrote:Note that Dark_Alex said he was not working on 6.00 M33 and that for the moment, no public 6.00 GEN is still expected.

But..on to the article

Translated source

The firmware 6.00 will not put up a big resistance and this will enable us to review the differences between the old and the new firmware generation.  (see the New Hidden 6.00).since the advance is certain and the firmware is now fully decrypted and it helps to push further research on it.

The differences between the KD folder of 5.50 and that of 6.00:

The PRX system directory that you all been updated and here too there is a change.  
Note the appearance of PRX following: codec_01g.prx, codec_02g.prx, codepage.prx, libgameupdate.prx, libmp4.prx, mlnbridge_msapp.prx, mp4msv.prx, np_campaign.prx, power_01g.prx, power_02g.prx, umdcache. prx, usb1seg.prx, usbdmb.prx) and disappearance of others codec.prx, idmanager.prx, impose.prx, power.prx, umdcache_02g.prx, usb1seg_02g.prx

The first stage of the discovery of 6.00 has therefore been reached and our team of developers fetishes will therefore continue its investigations to try to bring us more information about this topic.  Note that Dark_Alex said he was not working on 6.00 M33 and that for the moment, no public 6.00 GEN is still expected.