Michael,
We are talking about two different things. The "Sites" listing of web sites that use OpenACS does not need a link back. Although it would be nice.
We are talking about the Companies list which should list companies that can help someone implement a web site using OpenACS. That is companies that offer OpenACS consulting. So yes, I think if we link to a comapny saying "if you need help with OpenACS, these companies can help you", we can expect that the companies in the list will actually say how they can help with OpenACS.
