The problem du jour was that we ended up triggering Google’s Badware filter which meant that anyone visiting the site from Google got a warning that the site contained badware which might damage their computer. Needless to say pageviews dropped a bit!
I logged in the Google Webmaster Console as soon as we got complaints and checked it out. It said that the homepage was an example of a page with a badware problem. The only two external links on the homepage are to Adult Friend Finder (via my affiliate account) and a banner ad from a very reputable network ran by one of the largest companies in the world.
So I complained to Google and within an hour or so they’d removed the badware warning, so overall I’m quite happy with their response.