I am on 3.0 and jailbroken. I have the categories app and I have apps in folders as well as apps on their own on pages. Then, I noticed my battery was running a bit low so I wanted to turn off as many things as I could in the settings. I'm pretty sure I only turned off wifi, location services and restrictions but when I exited the settings I noticed all the apps that were usually in the folders had been copied to the pages. Now there are 2 of each app.. understand? I've reset but that did nothing and I would sync again but it would take ages cos i've downloaded heaps of apps since I last synced.