I did try D when it was in its early days (i.e. D 1) but at the time I was put off by lack of documentation, the standard library split (phobos vs. D) and general immaturity of the system. I'm sure things have improved since then but I really like Go's simplicity.

I've written some hundred thousand lines of production code in Go and D and feel they are very different languages. To sum it up: Go is a better C while D is a better C++.