To understand a language, one must know what problem it was designed to solve. It isn't always obvious, or what it initially looks like it was designed to solve, or even what the community thinks it was designed to solve.
Erlang, for instance, isn't about concurrency. It's about reliability.
Go, I think, is also not about concurrency. It's about building a language that can be sanely used by reasonably large groups of people of varying levels of skill, yet still produce fairly good software even so, without the language forcing a complexity explosion to deal with it.
Consequently, this does not appeal to a lot of relatively skilled programmers used to programming alone. It isn't my personal pick of favorite language, for instance. However, if I could push a button for free, I would convert my workplace of a couple hundred developers to it in a heartbeat, whereas I probably wouldn't actually do that with my favorite language. It is not, of course, a magical fountain of code quality, but it would give me the best tools and best foundation to clean up code bases that in all the other candidate languages I know are one or another sort of mess.
If I were starting a new startup right now and Go were even remotely appropriate, I'd use it. But in my hobby projects? Not really. Except maybe to smash out a microwebsite, it's pretty good there.
So, you know, a lot of the question is what exactly are you looking for in a language? I like Haskell, but the idea of even proposing to change a project at work to it is laughable... and this is important... nor would I expect to enjoy the result two years later if I won. The mess of code that would result from people hitting Haskell with a stick until it did what they wanted it to do would be an unstoppable torrent of ill-conceived code. On the other hand, Go would almost certainly produce much cleaner code, because that's where it really shines. Maybe it isn't "good", but it's the best choice right now in a lot of places.
(It's interesting to contrast Go's approach to this problem with the other major language to tackle this problem space, Java. Despite attacking the same problem, the approaches are significantly different, and I think Go's way better. I'd hesitate to actively predict this, but Java could definitely be feeling some heat from Go in three to six years in a way that very few languages have actually managed to provide any challenge to Java in a long time.)