Off all the top performers, Go seems to be the only sane choice to write a web app. Moreover it is at the sweet spot; expressive, flexible, simple, super performant, good community etc. I think it is convincing enough for me to give Go a serious look for our new app.
As someone who is also really enjoying Go, I think you need to add a huge, gigantic disclaimer before making a statement like this: Go's ecosystem of web development packages is in its infancy. You're not going to find any super-well-documented, super mature/stable web frameworks (thought a few are showing great promise). and some of the individual components (for example, Gorilla) are looking very good, but still ha…
I've read about the limitation of Go in terms of third party libs, but I believe it is only temporary. I had a glance at the std libs, looks really good for a new language. Our new app doesn't require all the bells and whistles of a full fledged framework.