Currently Being ModeratedJan 27, 2013 9:01 PM (in response to chudlychudson)
This was driving me crazy too but the post above about photos got me thinking.
The symptom I saw was that iTunes thought I had 4GB free but when I clicked off of the device pane and onto Books (or another part of my library) it turned to 3GB, showing that something was being changed behind the scenes somewhere.
So I went back to Photos pane on the device info and saw that iTunes had decided to no longer sync a photos folder I had set for that. Reenabling that option on the page and confirming the change has now eliminated the Revert / Apply jazz, for now at least.