(You left out "// +build", which predates Go 1.4.) We made the decision that "//go:" is the syntax for comment directives. The old ones stay around for compatibility reasons. Previous discussion: https://groups.google.com/forum/#!searchin/golang-dev/commen...
All of these of course are minor things. Go does a lot of things very right like easy of concurrency, scope and quality of the standard library and easy of deployment. Looking forward to the GC improvements in the near future as well as a day when we get generics. I'll be a happy camper then.