Is gmail planning to introduce new domain names?

I have a gmail account. Today, when I signed in and then signed out, I suddenly noticed that in the 'username' field it is now showing my full email address. This is instead of just username. So, 'user@gmail.com' instead of just 'user'.

If I am not imagining things and that was the change, then there is only one reason I can guess for that. Gmail is planning to introduce additional domains (as mail.com did) and automatically substituting full address for login is a transition step.

Any guesses on the additional names? Gbrowser anyone?
BlogicBlogger Over and Out