When searching for an email address in Gmail, in addition to person’s profile image and past conversations, you will now see the person’s contact details like email, phone number, and quick links to start voice and video chats. Google noted the contact data would automatically stay updated for users who have a Google+ profile.
Google has integrated with Gmail through a number of ways in recent months, but today’s update brings further integration with the ability to use Circles in search and filters by typing circle:[circle name] or has:circle. The update also adds profile photos of people in any selected circle in the upper right of the page. The new features will roll out to all Gmail users today.