To continue, I want to grab the news I just read. Datel may had success in cracking the PSP's encryption process and sign EBOOT's to run their own software on official firmwares, including the newest and the PSP Go hardware.
Why do I post it as I only focus on PS3 you may wonder, but hey the PS3 just got it's PSP emulator to be able to run the PSP Minis. I didn't do any research on that yet, but well I guess it's the same as with the normal PSP games you could play on the PS3. The package file is extracted to PS3 HDD and runs the unpacked PKG files including the PSP EBOOT.BIN.