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Sony has just released the version 2.6 firmware for the PSP in North America and Japan.
V 2.6 will allow support for Microsoft’s Windows Media Audio files, though you won’t be able to play WMA 9 Pro or Lossless versions.
It will also allow you to have RSS channel support for podcasting with MP3 and MP4 (AAC format). It will also let you write copyright-protected video to your memory stick.
The firmware upgrade is available on the US PSP site along with full update features.