I wish there was an e-mail or phone number I could just speak with someone about this directly, but...
When I went to finalize my order for the Season 2 DVD (after already purchasing the full season and getting them as they were released), it came up with two errors:
# Your billing address could not be verified. Please make sure all of your information is correct.
# The billing address you entered does not match the card. Please double-check the address and try again. If it still doesn't work, contact your bank.
Come to think of it, I may not have changed the address on my credit card since moving home for the summer. Would that be why I'm getting the above errors?