Since some days, the "OpenJDK Build README" mentions Visual Studio C++ 2010 as the reference compiler.
As mentioned by Kelly (http://mail.openjdk.java.net/pipermail/build-dev/2010-May/002944.html), the step seems to be a stable one, at least for some years, I guess. Kelly, to your knowledge, has the transition to VS2010 been adopted even by the formal JDK7 Release Engineering team? Can we, outside of Oracle, give it a try or should we better wait some weeks to see the build process stabilize before risking our mental health ;-) ?