Wii owners can expect to see their console emitting blue today (assuming they have Wii Connect 24 set to on, of course). Nintendo delivered today Version 3.3 of the system's firmware.
This appears to be a tiny update -- hence the fractional number increase. The only change listed at Nintendo's update page is that you now have the ability to move the Miis in your avatar lobby into an avatar parade.
You can update your Wii by powering up the system and selecting update from the main interface.