Google+ is a huge network like Twitter or Facebook that lets you create circles of influence or interests, whether its healthy living or cooking or actual friends and socialize with them or see their recommendations on things.
If you add a few people to your Google+ circles (as many as you like), you start seeing things like "Michael T. Babcock recommended this" when you browse apps on your phone or "Cindy Babcock +1'd this" (similar to Facebook likes) on websites.
One of the best Google+ features is just browsing plus.google.com and using search to find what other people are saying about stuff publicly. Whether you're interested in talking to other people about making gluten-free pizza or how to fix a car tire, you can find them by just using the Google search feature on G+ and be social..
Google+ is a huge social network about sharing thoughts, ideas, etc. without being about friendships or relationships.
Facebook is about people you know. Google+ is about stuff you want to socialize about. I use Google+ hours every day socializing with people about everything from computers to religion to politics and random world events. I only post on Facebook about my family. I can even link to my public posts on G+.
Google+ is also asymmetrical -- you add people you're interested in following, like Twitter, you don't "friend" people. They don't have to care about you back for you to care about their posts, which makes it excellent for celebrities (many of whom use it) and news makers who have no interest in following their fans but have things to share with them nonetheless.
Personally I say give it a shot -- you don't have to share anything at all, you can just sit around and lurk and optionally comment on other peoples' posts.
This was originally a reply to someone on Facebook and I re-posted it here for public consumption.