Been having this issue for awhile now, over multiple devices. Started noticing my battery flat after about 6 hours and when I checked my data for this monthin, a week and a half in I was already at 2.1gb. When I check the phone, its constantly showing data active, and when I can actually get IN to the battery manager, Android System is constantly showing a large amount of data sent. Example, its been unplugged for about an hour and a half and it's already uploaded 35mb worth of data. Yesterday, it was at 130mb in the afternoon when I did a factory reset. I've caught it higher than that. Not rooted, running 2.2, the only widget running for data is beautiful widgets home. No other widgets that sync are running (only widgets at all are messages, calendar, pdanet and the sticky note one, plus some contacts).