Hi everyone.
Lately I experienced the same trouble/issue with iTunes and my iPhone 4S as well as with my iPad mini, both running iOS7.0.6.
The weird thing was that iTunes recognized my old iPad 1 running on an older iOS.
So, the WiFi syncing worked for the iPad 1 and at the same time iTunes would not sync my iOS7 units - only when attached to my iMac through USB-cable.
The iMac´s OS is Mavericks and the latest iTunes 11.1.5.
After hours of trial and error (like everything possible explained here, in other forums and almost every support page I could find) as well as many hours and quite some sessions on the phone with Apple support (who couldn´t help me either) I finally got both - the iPhone 4S as well as the iPad mini - back to regular WiFi syncing by simply restoring/resetting both units with iTunes.
So, the iOS software has been freshly installed.
And after a regular backup-restoring directly from my iMac using iTunes everything works fine again.
Simple as that.
Maybe for some of you this might be helpful, although it takes some (waiting-) time depending on the size of the data/backup to be put back on the devices.
Might be interesting to know that the problems occurred after upgrading my Iphone and iPad mini directly on the devices with the iOS7.0.6 that has been downloaded wireless to them. The direct download/restoring with the iOS directly from the iMac via USB-cable seemed to be the difference that solved the issue.