Microsoft is planning to include a lot of new features and improvements in an update coming within the next month or so, and today a new bug has emerged that they'll probably want to fix in that upgrade, if not sooner.  A user over at Windows Super Site is reporting that his AT&T WIndows Phone 7 device has been sending huge chunks of data over 3G, even if WiFi is available.  Between Nov. 21st and 24th, the device sent 30-50MB of data at the same time every day, and did it again between Dec. 1st and the 4th.  Finally, after running on airplane mode for a few days, the phone's data connection was switched back on and it promptly sent a whopping 400MB of data.  Windows enthusiast Paul Thurrott confirmed the problem, although he wasn't sure what exactly is causing the problem.

Considering that a lot of Windows Phone 7 users are on AT&T, a carrier that notoriously got rid of its unlimited data option last year, this issue is something that Microsoft needs to take care of quickly.  In the mean time, WP7 owners, especially those on ATT, should closely monitor their data usage.  Are any of you out there using Microsoft's mobile OS and noticing that your handset is sucking down big chunks of 3G data when it shouldn't be?

Via WPCentral, WinSuperSite