Here is the text of the message I recently sent to the JSR 255 Expert Group, in my capacity as Specification Lead.
I'm sure that you saw some months ago that our work on JSR 255 will not be part of the JDK 7 release (http://openjdk.java.net/projects/jdk7/features/). This decision was made here at Sun in order that some of the higher priority features could be properly resourced, in particular for the TCK work.
So, we need to retarget our work for JDK 8. This note is to give you an update on how I plan on handling that properly.
Over the next month or so, I'll be setting up a new OpenJDK project called "JMX2" where the Reference Implementation work for JSR 255 will live. This means that all our specification and RI work on JSR 255 will continue to be available to all to evaluate, critique and try out, and it will be up to date with the stable JDK milestone releases.
In order to do this, I will prepare a big changeset (call it the "undo changeset"), which will change the JMX API back to what it was in JDK 6, and apply that to JDK 7. Then, I will kick off the new workspace as a clone of the JDK 7 repository, including the undo changeset. I will immediately apply a "backout" changeset that undoes the undo (using Mercurial's backout command), so JMX2 is where JDK 7 was before I started.
I hope to have better news about making progress with the TCK as the JDK team starts planning JDK 8, which is likely to be towards the end of the JDK 7 cycle (http://openjdk.java.net/projects/jdk7/calendar/), at the beginning of next year.