> Do you work at Google?

I did for over 5 years. While I left before the Go programming language was released, I seriously doubt they've transitioned much of the codebase to it, for one simple reason:

The Google codebase is fucking massive. I simply cannot describe how unbelievably huge it is, and while I don't doubt for a second that Go will be used for some of the systems-level projects (some of which Rob Pike is directly involved with - how's that for vague), you simply don't transition that big of a codebase to a new language.

It would basically be impossible... unless you're Jeff Dean.