I was so happy this morning when I visited Nintendo's press page and found out what Satoru Iwata has announced:
As the library of downloadable WiiWare and Virtual Console⢠games continues to grow, Wii owners have asked Nintendo to provide easy, expanded storage space. Starting today, Wii owners will be able to save downloaded WiiWare, Virtual Console video games, and Channels directly to High Capacity SD cards, in addition to SD memory cards. To play games that have been saved to SD cards, consumers will be able to select and launch them from an SD Menu icon on the Wii Menu. (Note that when launching games or channels from an SD card, an equivalent amount of internal Wii memory is required. To clear space from the internal memory, users can transfer games or channels from the Wii Menu to the SD card). This feature is included in the latest version of the Wii System Menu Update, which owners will receive immediately after performing a system update today.

All I can say is, "it's about time!"
I have been doing the "SD card shuffle" for months now. I have a 512MB SD card that I move content from the Wii system memory to all the time. When the SD card fills up I move any low priority content to my computer. I know I can always re-download the content but some content includes save-game data. If I have invested hours playing a game I don't want to have to do it again if I don't have too.
I have not taken the time to download the update myself so I don't know if everything can be moved and played to the SD card. Those who know me know that I am a big player in the Pokemon world. As such I have a copy of My Pokemon Ranch on my Wii.
The My Pokemon Ranch software can not be copied to an SD card and for good reason. If you were able to copy it you could then copy it to your computer and use this method to clone Pokemon in minutes. Because of this I expect that the update will not allow some content to be moved off of the internal Wii memory.
It is also important to note that this update still uses the Wii internal memory to run the content. What this means for some of us is that if we buy a lot of content that can not be moved to the SD card it will suck up system memory and possibly prevent us from playing some games that are on the SD card if a like amount of memory is not available on the Wii itself.
In all I am very happy with this announcement. We have long been itching for more storage space on the Wii and this answer from Nintendo is a step in the right direction. It's not perfect but at least they are not going the Microsoft way and forcing us to buy a locked down drive expansion at an inflated price. (MS HDs for the 360 cost more than $1 per GB while most HDs cost < $0.20 per GB.)
There were a bunch of other announcements involving WiiWare and the DSi but the only important announcement was the one about Wii storage.










I got it.
You copy the game files themeself to the sd card and only need 1 game space on the wii as the games temporarily go onto the wii when loading to save time.
The save files stay on the wii so make sure to keep the save files on the wii as games won`t pick up save files from the sd card.
Also you can copy ranch to the sd card to save space but you can`t copy the save data. This goes for games aswell like PBR,SSBB etc.
I agree with your “It’s about time” comment. It’s surprising it took this long. This will be really nice.
Storage has always been my biggest gripe with the Wii. I was worried they might go the proprietary way (360 drive) but they didn’t.
To be honest when the Wii came out with SD Card support I was shocked!