Agreed. As long as the Java is fully and accurately documented, I'm not overly concerned that the JVM be open source. It would be somewhat helpful if they'd open up the browser plugin code, as there doesn't seem to be a whole lot of movement on Sun's part on that stuff. Perhaps the community can bug hunt for them.
Perhaps opening up the code will be good for their JVM. The jrocket JVM is already lots faster on intel boxes (with some really cool probes available to monitor running code). We're looking really closely at migrating some of our Solaris-based WebLogic servers to Intel boxes running with the jrocket jvm.
Ugg dont get me started on BEA's cluster*&^% of a support matrix..