I just answered your same question over at RIM Forums.
If it's showing in Desktop Manager then USCC has approved it for you. You can intall it, however, I recommend installing it manually.
Use this link and just follow the instructions in the first post. The download isn't from USCC but it's the exact same OS. This type of upgrade is more reliable. Do make a manual backup with Desktop Manager and then do the upgrade with Loader.exe as instructed. http://www.blackberryforums.com/gene...630-5-0-0-801-