Here's an interesting blog post by Jill Corcoran Books talking about a book's jacket cover and how that sells books. Very interesting, since I was just in Borders on Saturday and found myself looking at jacket covers, trying to figure out what books were about just by looking at them. If the jacket cover interested me, then I flipped it around to read the synopsis. So I have to say that as a consumer I find myself judging a book by it's cover (unless of course it's an author I already know, or the book has come recommended).
So, it's something to remember for the future when the book is published.