IMHO, if you are not on google+, you might as well hang up a going out of business sign.
Granted, I think G+ is the least user friendly, most confusing, and lamest of all the social media platforms, but it’s owned by google. And it’s free to use.
No, not as much as some think. All that is being done in this thread is building a (friendship) network.
What works, is placing a Google+ button on EVERY PAGE of your website, and having everyone click the button on EVERY PAGE of your website.
Ever notice on Google searches you see some results with the Google+ links and often pics of those links? That is the result of clicking the button on websites. Every click on EACH PAGE is a vote for EACH PAGE THAT IS CLICKED by the consumer viewing EACH PAGE! In effect, EACH PAGE that is clicked, will return results higher than those not clicked. This has been stated many times on this and other MB’s, but many just refuse to install the buttons for best effect… ON EVERY PAGE of their websites.
Somewhere on this MB is complete instructions from Dominic and others as to how to do this.
Now, with that being said, it certainly won’t hurt to do what this thread is stating to do, and it won’t hurt to tie in “SM” links to your site, BUT… these do not have the SEO juice that many believe. Google is too smart for those tactics. Bottom line is… they want QUALITY sites that people actually go and spend time on. When these visitors vote on a websites page by clicking the Google+ button, they are saying they approve of THAT PAGE, not the entire website that page is contained in.