Thanks for the info, didn't realize they launched this feature as well. I doubt it will take them long to bring it to Go.
GvR mentioned today at Google I/O that the Go runtime was championed by another group within Google. Apparently, the same thing happened with the Java runtime before it was brought into the App Engine team. He expected the same thing to happen with the Go runtime. So one would expect new features to come to the Go runtime slightly after the other "first class" runtimes (Python and Java).