Even if you're a fan of SlideShare, it might surprise you to learn that the service has been around since its inception in 2006. The presentation-sharing platform (owned by LinkedIn) announced last week that it's making many of its Pro level features free.  The change took effect on August 20, 2014. While that's obviously great news for SlideShare power users, I feel that the majority of marketers take content on SlideShare for granted [...]