Not yet, but as I mentioned in #20546, I am discussing this with some of the other GHC devs and working on getting the changes upstreamed. None of the core folks have access to 10.9 right now though which is a problem, so testing would help here. Also, once the changes are upstreamed, it will still probably be a relatively long time before they arrive in a release version since, from what I can tell, the current plan is to focus primarily 7.8 now.

The changes are minor though so I don't think there's a problem using them. Like I said in the notes, there is a possibility that the DTrace RTS functionality will need further fixes. I haven't had a chance to test this yet. Regardless, it is a feature that a very small minority of Haskell users will ever use (or even know it exists, for that matter).