ok i don't think podcasts was the cause of our ghost usage (as we didn't have the app) however i will test it last to see. i have a feeling its the icloud from what i've seen elsewhere online but time will tell.
oh and interesting read that link - http://alistairfairweather.com/warning-all-iphone-and-ipad-owners-ios6-and-i
oh and interesting read that link - http://alistairfairweather.com/warning-all-iphone-and-ipad-owners-ios6-and-i