Credit cards are only part of the problem. If your site can be hacked, then the hackers can: 1) upload scripts to send unsolicited email, getting your IP addr

Credit cards are only part of the problem. If your site can be hacked, then the hackers can: 1) upload scripts to send unsolicited email, getting your IP address banned. 2) upload scripts to scan the internet for other targets (most common---an SSH scanner) 3) modify the HTML output to leak Google Page Rank to questionable sites, which risks your Google Page Rank. 4) passwords of users, who typically use the same password on other sites. 5) setup an illegal file trading section, hidden from most users (anything from music and films to kiddie porn (saw this first hand, and what once was seen can never be unseen---shudder)) 6) IRC clients to control botnets. I've seen all of these first hand working at several web hosting companies. It's more than just "credit cards."