Jan 30 2008
PSP 3.90 firmware now out (Updated)

If you own a slim PSP, you can finally download PSP firmware 3.90 and Skype all you want. Of course this requires the PSP headset with remote control, and this is not available for the older PSP models as they lack the processing power for proper VoiP calls.
Access it through XMB’s “Network Update” menu.
[Update]: Now you can download the custom firmware 3.90 M33 just a few days after the release of the original firmware. Visit Dark-AleX’s page for download links. If you already have 3.80 M33, you can just use the “Network Update” menu to get the latest goodies.