The zombie infection itself seems to be very complex and designed to be loaded in pieces. Apparently 300 or so infected websites are disseminating the virus to visitors that use those websites. The virus then goes out to the web and pulls several pieces of information it needs to attack the eBay accounts.
Aladdin Knowledge Systems claims there are 4 or 5 stages to the Virus to gather everything it needs to launch and participate in the attack. It is currently unknown how many machines are infected and participating in this attack. Aladdin Knowledge Systems first noticed the botnet attack when it was discovered by their eSafe SecureSurfing product that is marketed to ISP's to monitor and filter infected websites.
Additional details, including any database compromises, have not been disclosed.