A few days ago Vic Gundotra, the executive in charge of Google+, announced that he's leaving Google. That triggered a huge kerfluffle of people pronouncing Google+ to be doomed. Even TechCrunch got in on the act with a an article Google+ is Walking Dead. Balony. Google+ (or something like it) will be with us for a long time for one simple reason:
Google+ (or something like it) is integral to the future of Google's core product, Search.
Remember when Google started? Your website's page rank was based upon the number of links to it from elsewhere on the web. As time went on, Google's page ranking algorithm has evolved quite a bit but it still relies upon the number of links to your website. Unfortunately the landscape that made that a valid metric is changing, and may well be in the road to obsolescence.
Consider that if I add a link from my website to yours then I'm 'voting' for your website. The more votes then higher up in the search results you appear. The problem is that most of us don't vote that way any more. A small percentage of people have their own personal website. On the other hand, almost every one has a Facebook page, Twitter profile, etc. Today we 'vote' by sharing a link to your stuff on our Facebook page. We call this social sharing.
If Google's primary product - Search - is going to stay relevant then Google must
figure out how to include social sharing as a factor in page ranking.
There are really only three ways that Google can do that:
1. Learn to play nice with Facebook, Twitter, Instagram, etc and avail themselves of the social sharing metrics of those companies.
2. Acquire a new or existing social media company.
3. Make Google+ (or something like it) sufficiently popular to provide Google with the metrics it needs.
That's why I think Google+ is here to stay.
Frankly, I think that Google would be foolish to pull the plug on Google+ right now. Google + Communities are far better than anything that Facebook has to offer. They are active vibrant online communities, each one focused on a specific topic and populated with people who are passionate about that topic.