I just got through cancelling mine. I can say changing credit card info doesn't work. It verifies that the number you use is good when you save it. And changing the card's expiration date won't stop them from billing you. I changed my card's date a year ago and they never stopped billing, they just kept sending me an email saying the card was expired. The one time I changed the CC number to a card that no longer was valid, they not only stopped billing, but they totally locked my account making me unable to login to xbox live even as a silver member. It would log me in, say account invalid and log me out. I had to put in CC info just to be able to connect, update my gamerscore or message a friend.

To cancel the account you need:

1.)All account info. You need your name, your user id. your accounts telephone number, the last four digits of the CC, the full address on the account. If you aren't the credit card holder you also need them there. If any of these above items does not match their records they will not cancel the account.

2.)Call 1-800-4MY-XBOX

3.)Wade through the automated messages (it's not one of those press a number options, you have to say the name into the phone).

4.)Get a service rep, and essentially fight them over cancelling the account. I think I was asked three times why I was cancelling the account. They even asked if there was someone who was willing to pay for the account for me.

Go to them ready for battle. Make no mistake, they do NOT want you to cancel your subscription. They have made it as difficult as they possibly can just for that purpose. It's a shame that Microsoft does this. It reminds me of the Hitchhiker's Guide to the Galaxy. Where the plans for the freeway that was to run through Arthur Dent's house had been on display and open to debate for a month according to the commisioner. Unfortunately for Arthur they had been in a dark basement with no lights underneath the town's city hall.