Expanding upon the original Wii Fit software, Wii Fit Plus is packed with every feature from Wii Fit—plus new exercises and tools to personalize your exercise routine.
If you already have a profile on the original Wii Fit, you can easily transfer it over to Wii Fit Plus.
For the past few days, I've been, on a whim, trying to update my Wii system, just to check out the SD card update you know.
To see if it's any good, whether or not I'd like it, nothing too big.
Note that USB thumb drives and flash storage are not recommended as external storage on the Wii U; Nintendo has explained that because flash storage has a maximum number of reads/writes, it's unsuitable for the type of continuous data access needed to run games.