add note about go versions

README.md

@@ -5,6 +5,11 @@ go-github is Go library for accessing the [GitHub API][].
 **Documentation:** <http://godoc.org/github.com/google/go-github/github>  
 **Build Status:** [![Build Status](https://travis-ci.org/google/go-github.png?branch=master)](https://travis-ci.org/google/go-github)
 
+go-github is tested using Go version 1.1.  There are have been
+[reports][issue-9] of JSON marshalling errors using Go 1.0.3, at least on
+Windows 7.
+
+[issue-9]: https://github.com/google/go-github/issues/9
 
 ## Usage ##