VisitorBoost is not a scam. They sell unique visits from full-screen popunders on the Adversal network. There are no bots -- a quick look at the HTTP headers or tracing the IPs would disprove that. They're real visitors on normal ISPs visiting publisher sites in the chosen topic category.
Whatever blank registrations you got were probably from spam bots, not part of your advertising, trying to exploit the registration form on your site to send spam mail. Every form on the web is eventually hit as they just crawl sites looking for forms to submit to get spam out (header injection and such).
I manage VisitorBoost.com. We've been selling this advertising for more than 4 years now and have over 20,000 satisfied customers. It's unfortunate that a few don't understand how popunder advertising works and post things like this instead of asking for help.
Clearly I'm not a regular member around here, so I'm sorry for bumping this old thread. It shows up in search engines, though, so I'd prefer to have both sides to this story preserved.
