I know that Go support for appengine is marked as experimental, but being linux/mac only for half a year, without any roadmap for window support is exactly what I call half hearted.

And full windows support for Go wouldn't be that hard. Many open source projects have windows support thanks to mingw/msys. Having Go and Go appengine fully supported on Windows wouldn't take more than 1 full time engineer. If that is too much to ask for Google, than Go is not even half-hearted supported.

For android, I know that it would be a bad choice to bridge it to Java UI framework. I was thinking of having native Go SDK for Android that will have its own UI and other API, which doesn't have to be similar to Java. Gooogle has already separate appengine SDKs for Python, Java and Go. I know that it would be a lot of work to do the same for Android, but that will at least show that Google is really pushing behind Go.