This post is part of the 'Market Intelligence' series, brought to you by SimilarWeb: get insights for any website or app.Adult Entertainment is one of the leading industries driving website traffic online. But just how much of this traffic is coming from adult websites, and where is it coming from? We teamed up with SimilarWeb to explore the murky world of online porn consumption. The results may surprise you – and also provide fresh perspective on how online marketers working in this category maximize their returns. Adult websites are responsible for 4.41 percent of all desktop visits in the Internet worldwide (in Feb 2015). To put that in perspective, ExtremeTech surveyed usage data pulled from Google’s DoubleClick Ad Planner, and discovered…