Apologies for the delay in responding your tweet--I found it here(https://twitter.com/edent/status/415537481829068801). I'll get back to you over Twitter as soon as we've removed you from the index.
We are working on a set of tools to allow engineers to manage their profile on Sourcing.io (and opt out)--I hope that they'll be good enough to encourage you to re-join.
Please, I urge you to move to an opt-in only model. Otherwise you run the risk of being as despised as Klout and other similar forced participation sites.
I completely understand your perspective. The problem for companies who want to recruit great people is that most of them aren't looking for new a job (several studies put the percentage at around 80%). Therefore, companies are forced to reach out to those people to pique their interest. There's a subset of great companies who take the time to craft personalized, relevant emails to these people; there are some who even get their engineers to write the initial email. We want to work with these kinds of companies.
Right, then they're not looking for a new job. What part of that do you not understand?
That said, opt-in is the way to go. I definitely don't understand the seemingly contradictory point of view of them saying "we don't like recruiter spam either" and "we find ways for companies to send unsolicited requests".
So, I would fall under the categorization of "aren't looking for a new job", while at the same time don't agree with the opt-out (without an actual opt-out mechanism) nature of this service.