Hi,
I'm the lead developer of Spamagogo. I assure you, we're genuine. Also, we're not affiliated with any of the organizations you mentioned, our spam filtering is done using our own technology, which is a collection of various techniques such as bayesian, ip-based blacklists, and collaborative filtering.
Anyway, do you think that there is anything we can do to our website to help people feel better about using it?
Thanks,
Matt Miller
Lead Developer, Spamagogo
http://www.spamagogo.com