I can't answer your question directly because all of my transactions on e-Bay have been purchases rather than sales. (100% feedback, I'm glad to say). Some of those purchases, however, have been from people with no feedback. The reason I've been happy to make these purchases is that they've always been for small amounts (�1 to �10). I've known that that there's an increased risk dealing with someone new to the system but, because of the small amounts involved, I've been prepared to take that risk.
So, if you're hoping to sell, say, old postcards, without any feedback, you might well get some takers. If, however, you're hoping to sell, say, an expensive digital camera, then you might have difficulty in attracting bidders.
As I've said, this doesn't answer your question directly but it shows that there are some people out there who've managed to get sales with no feedback - because people like me have bought from them!
Chris