Google is moving forward with the Google+ integration into, basically, everything else it has. One of the smaller recent updates is to the profile cars in Gmail, the small overlay that pops up when you hover over a contact's name. The new profile cards are more interactive and enable users to do more Google+ related stuff straight from Gmail.
For example, they can add contacts to their appropriate circles, start a Hangout or just visit the full Google+ profile. Another neat addition is the link to list all emails from that contact, which makes it easier to see the bigger picture.
"Now when you mouse over a person's name, the profile card that shows up has a cleaner design and new integrations with Google+. You can easily add people to your circles, navigate to their Google+ profiles by clicking on their name, and start a Hangout," Google said