Gmail Now Lets You Email Your Google+ ConnectionsJanuary 21, 2014
Google announced the new integration between Gmail and Google+ that suggests your Google+ connections as recipients when you are composing an email. Google now lets you control the way people are able to reach you and extends your connections. You can choose between anyone on Google+, Extended circles, circles, and no one.
The new feature will keep email addresses private unless you send a reply to an email. Your email address isn’t visible to a Google+ connection unless you send a reply. The reverse is also true: his or her email address isn’t visible to you unless he or she replies to your email.
To avoid an abundance of annoying emails Google says that the latter emails will only be sent once: the person can’t email you again until you respond or add them to your circles.
Google says the feature will be introduced “over the next couple of days” to everyone that uses Gmail and Google+.
Be on the lookout and read more about the feature here.