And Go doesn't really qualify for any of these. For the latter 2 largely because of the GC.
I think in practice, that its engineering bent i.e. no frills language and high quality tooling, will more likely see it being used in the server-side application/middleware space. I guess not surprisingly.
So it really is up against Java, Python, Ruby and C++ and is, therefore, interesting in that it isn't trying to compete on lingustic goodies.
I'd say it's a better C, not a better C++ (or Java/C#)