PlayStation 3 (PS3) system upgrade will be released on April 1, 2010. The latest release will disable the “Install Other OS” feature that was available on previous game consoles.  Current users of the the “Install Other OS” feature can choose not to upgrade their PS3 systems, although the following features will no longer be available;

• 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

Additional information about PS3 firmware updates, including v3.21 (once it becomes available), can be found here:
http://us.playstation.com/support/systemupdates/ps3/index.htm