For me, I just don't see enough benefits of Go over C++. I already know how to use C++ in a way that avoids or mitigates the problems Go solves. With C++11 support starting to take off Go's advantages are even smaller.
On the other hand, if I didn't know C++ and I was looking for a native compiled language to learn, I'd probably choose Go over C++.
Depending on what you're doing, the libraries make a giant difference. Look over Go's standard library packages and then imagine what a pain in the ass it would be to find and manage all the separate C/C++ libs it would take to replicate all that functionality (or to write it yourself).
On the other hand, if I didn't know C++ and I was looking for a native compiled language to learn, I'd probably choose Go over C++.