I have read quite a bit about the Go language, and it seems promising. The last important bit of information I am missing before I decide on spending more effort on the language is: How much money/man power does Google or other companies invest in the development effort? If this information cannot be provided, do you have any other information showing the commitment of Google to the project. Is it being used as the primary language for a new investment or similar (my guess is that it is too early for this, but I do not know)?
I have been using go for about a year now, and the language has continually improved since then. Things are changing, improving, (somewhat) stabilizing, and generally amazing me in their innovations (e.g. gofix). It is most certainly not dying, and they seem to be putting quite a bit of effort into it.
The Google code page shows 17 people contributing to the project. From the looks of it, all but three of them are likely Google employees: http://code.google.com/p/go/people/list. Worth noting is that the go project has notable programmers such as Rob Pike and Ken Thompson working for it, fathers of UNIX. If Google didn't care about the future of the go language, it is unlikely they would assign such high-profile programmers to its development.
Google is using go internally: http://golang.org/doc/go_faq.html#Is_Google_using_go_internally
The oracle saga won't happen with go: See the licence file and the irrevocable patent grant. Even if Google were to stop developing go (which is unlikely, given my points above), someone else would likely pick it up.
In addition to all of the above points, Google go is pretty much ideal for Google's internal use, due to it's built-in parallelization, native library support for the http protocol, and speed. For this reason alone, you can be pretty confident that go will be supported by Google for a while to come.
Recently Google invested another bit in Go and now Go runs on AppEngine. Another sign that Go is alive and kicking.
Upgraded from a comment by popular demand :)
I don't know the number of developers, but there's an intensive continuous development of Go. The team releases their improvements often (almost every weekly), maintains the documentation and the dashboard (http://godashboard.appspot.com/) and participates at the Google I/O and other conferences.
The community grows as well as the number of projects. So after a first hype and the trough of disillusionment Go now slowly gets up to a productive language.
How much is Google investing in Go language? I don't think any one could answer except Google itself.
Google has the habit of releasing projects and see how people react to them, if there is a lot of buzz around it, invest into it and if not, drop it.
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