Last I heard, 4-6 weeks ago, John was trying to have the 1st case at EJS but didn't know it it was a for sure deal or not. I'm guessing that sometime in the next year they'll be available.
I'm not sure it's going to be THE solution for everyone (obviously it won't be) but for some it's going to be nice. For rocks, the Doubler will still be it due to the lower gear, for general trail use, 3:1 will be great. I've had visions of High9's with 5.43s, my BBC/700 and a 3:1 205 in a new tube car.......