That update is safe to do. Nothing will be lost.
Though, if you still have 1.0.8, other aspects of your mod may be out of date as well. Have a look at our Softmod Any Wii guide (link in signature).
Be sure to back up any data on your SD card, as you will have to format it a few times, but when done, you can restore your data so you won't lose any of your apps, etc.