One might read this as Google+ being on the way out. I'm not sure it is, but it's certainly better than being compulsory fore gmail.

New Gmail users will no longer have to sign up to Google's flagging social network Google+, after 2 and half years of mandatory social account creation. Users previously had to sign up to Google+ when signing up for Gmail, Google Docs and variety of other Google products.

Whilst the company still encourages users to sign up for Google+ it now has a "No thanks" button when offering the service during the sign up procedure for its products.

Google Gmail No Longer Requires Google+ and Has "No Thanks" Button [itproportal.com]