This update does not affect any prominently-used features or menus; however it does provide some behind the scenes updates that will improve system performance.
February 25, 2008 (rev01)
- Disc Channel updated to display "Wii System Update" if the game currently inserted into the Wii contains a Wii Menu/Channel update.
- The Wii LED light will glow if information is received while playing a game
- Improve system performance
March 20, 2008 (rev02)
- Added WiiWare support in the Wii Shop Channel.
March 21, 2008 (rev03)
- IOS37 (the first IOS with the signing bug fixed) released. At this point it doesn't do anything, though.
If you have a System Menu below 3.2 and wish to upgrade, use AnyRegion Changer to update.
WARNING: Be advised that if your system is shipped with 4.0 preinstalled, you can not downgrade and will brick your console.
If you have a System Menu above 3.2 and wish to downgrade, AnyRegion Changer can do this too, and it appears to do a more thorough job than some other tools. See WiiBrew:FAQ#Downgrading?.