The demise of Google Reader's share features is affecting everyone from RSS-junkies to Iranian freedom fighters, and many of them are very displeased. Google Reader itself is very much alive and well, and in fact, the RSS reader will soon sport a slick-looking redesign. However, at some point this week, the ability to follow, friend and share links within Reader will cease to exist, as Google pushes people to use Google+ for those kinds of things. Along with it, the myriad communities that depended on Reader for years for everything from meeting new people to organizing protests will just have to figure something else out. It turns out Google wasn't so bad at social networks, after all.
This is a persistent problem with web services and particularly which are supposedly free. You are at the mercy of the service provider and they can cut any feature, change the service behavior, promote their new service over the one you are using or just plain shut down the service.