Andrew observed that the problem has to do with how the fact that "the clickable links in the Bing feeds the format http://www.bing/news/rssclick.aspx?redir= followed by the full URL of the site you intend to visit" and the fact that
"anyone can plug anything into the end of that URL and it will redirect to that site".

Click here to read the full WebRoot article – Spammers Use Bing to Bypass Filters, Spam Bad Links.

A trackback link from the WebRoot blog leads to an  October 22, 2009 article from GeekoPedia which includes a quotation from a Microsoft representative who stated,  “We were testing new features to improve the search experience for our customers, and during our testing, we found a bug that was causing this issue. We are taking immediate action and expect a fix in the next 48 hours.”

According to WebRoot some of the spammers were promoting fake news sites like the ones in the WorkAtHomeTruth write-up "Are Fake News Sites the Next Gold Rush?" – a play on the commonly used fake news site headline "Jobs: Is Working At Home Online The Next Gold Rush?".

The particular product that WebRoot mentions is one of the products calling itself "Home Business Kit for Google" which continue to pop up with new variations almost daily as discussed in Digging Deeper Into Hidden Negative Option scams here.

Of interest is when Adam says, "Personally, I don’t think anyone should be clicking any links received in email messages" which apparently would include even emails for which people have double-opted in including WebRoot's own email list here. Now maybe that wasn't Adam's intent, but that's how it certainly reads as of now. And honestly I've told certain people that their safest bet based on questions they've asked me at WorkAtHomeTruth is for them to completely disconnect their computer from the internet.

What's amazing to me is how quickly the spammers were able to exploit the Bing vulnerability.