Not yet, but it's now in the category of "You won't get fired for picking X". It's seen as enterprise-y and 'safe' and yes, is definitely quite used.

The fact it's used internally at Google and MS alone means it's got traction. I'm willing to bet lots of enterprise shops are using it for things, even if it's not #1.

The important question is would you have enough choices in Job Hunting if all you know is Go. And Go seems to be close to if not already a self sustainable status.