For those new to the game, mint.com can be quite handy for keeping an eye on transactions taking place across large numbers of cards/issuers. Mint doesn't currently track your AP & BB balances directly, but does cover just about everything else..
Originally Posted by
AlohaDaveKennedy
Watch all your cards carefully, especially if running transactions in volume. One consistent source of exposure is compromise of banking and transaction processing systems. AFAIK AP has not been compromised, but most of the major banks have and ditto the transaction processing systems.