I have multiple XBL accounts like most people, and I made one just about a year ago and used the free one month to make it gold. I used my debit card 1x since then to buy 3 months for it and I have not paid for it since. Check out this picture. It just keeps staying gold even though I only have $2 in my bank for the past 2 months.
:/ Yeah I see that now. It says "IMPORTANT! Microsoft Account Update Required to Avoid Interruption in Service" The email inside just tells me they tried to charge me and could not because I did not have the funds.