http://www.modmyi.com/forums/mac-news/677396-itunes-8-2-1-available-download.html
From some of the comments on page 1 it seems like it's ok to upgrade...but it's still early so I'd wait to be safe.
Updated iTunes on accident, iPhone won't sync. How can i get 8.2 again? Thanks...
Uninstall / delete itunes registry values for itunes.
Updated iTunes on accident, iPhone won't sync. How can i get 8.2 again? Thanks...
Hows does that get me 8.2 though?
Accident ?? 🙄
After you uninstall and clear the registry you go find an older version of iTunes online then just install that
I updated to 8.2.1 and the jailbreak went perfect (using redsn0w .8)