Sony are releasing a new firmware update for the Sony PlayStation 3 that will essentially cripple the ability of the older PlayStation 3 from installing another OS by disabling the "Install Other OS" feature.
Up until this update users had the option of installing the Linux Operating system on their PlayStation 3 to enhance what the PS3 was capable of. If you install the update, it will remove that ability. Sony say this is being done for "security" reasons.
* Ability to sign in to PlayStation Network and use network features that require signing in to PlayStation Network, such as online features of PS3 games and chat
* Playback of PS3 software titles or Blu-ray Disc videos that require PS3 system software version 3.21 or later
* Playback of copyright-protected videos that are stored on a media server (when DTCP-IP is enabled under Settings)
* Use of new features and improvements that are available on PS3 system software 3.21 or later
If you choose to run the v3.21 firmware update on your PS3 and do use the other OS functionality then you'll need to make sure you backup any files stored before applying the update as it will basically cut off access to that portion of the system once installed.
Although it has a release date of April 1 (April Fools Day) in the JST time zone, it is apparently true what they say in that JST (probably Japanese Standard Time rather than Joke Standard Time). Shame really although maybe there will be some work around eventually.
Full details at PlayStation.