I am running F10 on a couple other machines and have the auto check for update disabled as I want to manually check for updates. However, I just did a fresh install of F10 on a new machine and even though I have it set not to check for updates it continues to do so. I went in through the GUI - Preferenes > System > Software Update and have the following set:

Check for Updates: Never
Automatically Install: Nothing
Check for Major Upgrades: Never

No idea why this is still checking for updates. I am not sure of the specific file to manually update but if someone can point me in the right direction I would appreciate it. I know this isnt the first time that changes in the GUI are not reflected properly in the associated config file (networking for example). I should clarify that it is checking for updates but nothing is being automatically installed.

Try System > Preferences > Personal > Sessions, and make sure that "PackageKit Update Applet" is unchecked.

Hope that helps.

That was it. Now that you wrote that it did ring a bell as something I was missing. Thanks for that!