Updated to ITunes 10 now all 81 books to my ITouch every time sync

I updated to ITunes ver. 10.0.0.68. Then ITunes wouldn't recognize my ITouch. Got ITouch updates and now ITunes sees it and syncs, but every single sync it copies all my audio books to the ITouch even though they are already there! I use the "sync only checked items" but it copies every checked item, even if it is already there. If I uncheck it will be removed from my ITouch and I don't want that.

It takes a long time to copy every book I want to keep on the ITouch. Any way to revert to older version of ITunes or a way to stop it copying everything over each time? I tried "manually manage" and that didn't work either.