Interesting point John about ratings/vouching and having done no (actual) business with Bizniks.
I am in shoes akin to yours. I've never been paid by a Biznik for any services. And I have done business with only a few Bizniks (a few of whom became Bizniks after we did business, so would that count?).
But there are dozens of Bizniks for whom I would vouch (you, included), if the system were multi-dimensional with aspects such as:
High integrity, knowledgeable, generous, kind, bright, clever, professional, reliable, and so on. Character assessments that can be made by virtue of building relationships, aspects that are important to me in doing business with others.
I guess we'll see how this roll's out, eh.