Yes, Google now has its own social network, and it's growing by one million new users per day. Industry experts are predicting that by next year it will have grown to be the second largest social network on line - larger even than LinkedIn and Twitter.
Facebook will likely hold the No. 1 spot for a long time, though some people are predicting that Google+ will continue to outpace Facebook.
There are good reasons to get on Google+ right now (but you have to be invited by someone).
One thing that makes Google+ more valuable than any of the other networks - including Facebook - is its Circles feature. This feature allows you to group your contacts according to your own definitions. Then, you can share information only with the circles you designate. This is in contrast to Facebook where you can group your friends, but you still share your links and status updates with all of them rather than pick and choose the groups you share with.
I think Google+ has hit upon the one feature that every social networker in the world appreciates more than anything. You can use it to share information with your family and closest friends while shielding that same information from your business contacts. You can then share business information with your business circles and shield it from your family. That's true social networking and Google+ is working on the future. That's where you want to be today.