In just the last week, Nintendo has made 2 major updates to the Wii. First, several days ago they released the Wii System 3.0 upgrade. Features include:

-Digital Clock added to the Wii Menu right under the channel bar
-Forecast Channel now displays the current condition (cloudy, raining, etc.) directly in the Wii Menu in the Forecast Channel box
-News Channel can now show 2 scrolling headlines at a time in the Wii Menu, 3 when you click on the button
-Message Board now has the “Today’s Accomplishments” message as a white message which allows it to stand out from other messages
-Address Book entries can now be shifted around using A+B but only to empty spaces. Not too convenient.
-Calendar in Message Board no longer shows “Today’s Accomplishment” only days as having messages
-Scrolling messages in the Message Board now uses a different sound

Wii Shop Channel Overhauled (Visual aesthetic is the same, changes made to organization and browsing methods mostly)
-New Welcome screen detailing 4 Recommended Titles and the points they cost (gone is the title screen bar that had linkable games). The title bar can be clicked on to bring up a list of 20 recommended games.
-Titles You’ve Downloaded was moved to the main shop menu
-New ways to browse
-Popular Titles (2 pages of 10 and includes launch games so not only based on recent info)
-Newest Additions remains the same
-Search for a title which can use partial names
-Search by Category
-System shows the different systems and how many titles have been released under each
-Publisher showing different publishers and amount of titles released
-Genre (different genres listed and amount of titles under each)

Settings
-Warning added pre-system update detailing that technically modified consoles may cease to function upon being updated. Also the only way to not accept an update is to power down the console by holding the button for 4 seconds (the user can’t back out of hitting I Accept w/o powering down)

Also, the Wii now features USB keyboard support in both the Wii Message Board and the Wii Shop Channel. This means Nintendo has the ability to add keyboard features in future games.

This could imply that an Internet Channel update is on the horizon.

Images of the changes can be found here. 

Additionally, a new channel has been added to the Wii Ware section of the Wii Shop Channel. This channel is a special Metroid Prime 3: Corruption Preview Channel, that will showcase images and video of the anticipated game throughout the month. Hopefully this new Channel is a sign of more previews and possibly demos to come...