Quote from RebelKeith
Actually it is being worked on, they talked about it a lot at the last minecon, there is an hour long video of it on youtube. I'd guess it would be out around 1.7 (or 1.6 if we're lucky)
Oh, I know all about it. The discussion on the site they were doing all of the stuff on has been at a standstill for a long time. No progress has been marked. So either they haven't touched it, or one could assume that they are doing it in secret.
Of course, it's easier to choose the negative option. No possibility of getting let down later with the added possibility of being surprised by some sort of giant leap in progress!