I haven't been following any gaming news, so I don't know if this is widespread or not.
I checked my online bank balance this morning and last week Xbox live billed me twice.
Two charges, same ammount, same description.
I phoned them and initially they could not tell I'd been charged twice.according to the person on the line I had been charged on the 12th and that was it.
I told her I was looking at my bank balance and I could see that I had been charged twice. She put me on hold and when she came back she told me I had been charged twice and they would refund me for one of them.
I just thought I'd put this out there just in case anyone else got accidentally double charged and hasn't noticed.