The ebay.com home webpage has a link to their "Announcements" section, and it does describe their system being hacked, plus the type of information potentially compromised. See:
http://www.ebayinc.com/in_the_news/story/faq-ebay-password-change

Interesting that among the FAQ's it says:

"When did this happen?
Based on forensic research with internal and external security experts, the attack occurred between late February and early March."

So ... the hacked info has potentially been in the hands of the "bad guys" for over 2 months. On a positive note, the hacked password files were encrypted, so it should be more difficult to unscramble.