eBay will no longer allow sellers to make their feedback private.  The change is expected to go into effect on October 26, and sellers who continue to keep their feedback private, will no longer be allowed to list.  Here are the details:

Hi... I'm Brian Burke, Senior Marketplace Policy Manager for Feedback.

Feedback is the cornerstone of trust on the eBay marketplace. A seller's Feedback provides buyers the opportunity to make informed decisions about their bids and purchases. It helps instill buyer confidence, and it helps protect the marketplace against fraud.

We believe that buyers should have access to a seller's complete Feedback record before choosing to trade with that seller. For this reason we are restricting selling activities for members who have private Feedback. This is a global change and will affect all eBay sites. The expected date of this change is October 26, 2006.

What will change

-Members who have private Feedback profiles will no longer be allowed to list items after this change goes into effect. Only members with public Feedback profiles will be permitted to list items.
-Any items listed before the change will not be impacted. However, they may not be re-listed by sellers who keep their Feedback profiles private.
-Members who wish to make their Feedback profiles private can still do so. However, they must cancel any existing listings, and they will not be allowed to create new listings as long as their Feedback is private.

It's easy to make your Feedback profile public - just sign in and click on the "Make my profile public" option.
https://signin.ebay.com/ws/eBayISAPI.dll?SignIn&UsingSSL=1&pUserId=&co_partnerId=2&siteid=0&ru=http%3A%2F%2Ffeedback.ebay.com%3A80%2Fws%2FeBayISAPI.dll%3FFeedbackOption%26FeedbackOption%3D&pageType=565

Why we're making this change
eBay offers the ability for members to make their Feedback private as an option when they have significant concerns about a comment. They can hide their comments in this way until they are able to resolve the issue. (Read about Mutual Feedback Withdrawal).
http://pages.ebay.com/help/feedback/questions/mutual-withdrawal.html?ssPageName=CMDV:AB

Buyers should have all the information available about their prospective sellers' past trading histories. This helps them make knowledgeable choices about doing business with that seller. Prohibiting members with private Feedback profiles from listing items will ensure we help maintain a safe and well-lit marketplace.

Whether you're a buyer or a seller, your Feedback Profile is a valuable asset that helps earn the trust of other eBay members. We strongly encourage members to keep their Feedback profiles public so everyone in the marketplace can benefit from the Feedback other eBay Community members have left them.

Sincerely,
Brian Burke