Wow,?Pinterest?s porn section?is fairly tame. I was just curious about the type of not-so-mommy-friendly content that might be popping up on what?s now?the third-most popular social network?after Facebook and Twitter. (Also I?m bored). After all, Tumblr houses, like, a lot of porn. Both services aim to help their members find platforms for self-expression, one through pinning images for inspiration, the other through blogging, and both have also had to fight unwanted content on their networks.