While this update is recommended for Sony's Japanese PSPs only, the website does say that updates will be released for other regions. The downgrading of version 2.0 of the PSP's firmware was seen as a huge step forward for fans of home made applications or Homebrew on the PSP as well as opening the door for piracy. With this latest update the bug that allowed users to downgrade from 2.0 to the more Homebrew friendly 1.5 has been removed.
Unlike the upgrade from version 1.5 to 2.0 there are no extras included to entice users into an upgrade. While Version 2.0 had come with a web browser, 2.1 boasts only "updated security" which fixes the exploit used to bypass the security to downgrade the firmware. This allowed users to "buffer overload" their machine and rename the firmware to 1.0, enabling them to then "upgrade" to 1.5
Sony's stance against Homebrew applications is due in no small part to the fact that it allows a PSP to play copied games from CD image files (isos). This means that sales of both games and UMD films will decline as more users download pirated material. With nothing new to snare users, as there was with 2.0, Sony may be disappointed by how few people download and install the firmware update.
Rumour has it that 2.1 has replaced the download for 2.0 on Sony's official downloads page for Japan. While this is completely unproven for now, PSP users have been advised to be wary of where they download their updates.
If you own a Japanese PSP and would like to upgrade your firmware to 2.1 then the link is here. µ
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