Well Joe (Fatnoob) is waiting for the full 1.9 release, He doesn't want to spend time making a map on the per-releases or 1.8 and then have to make another one once it fully comes out. The full update isn't out yet so... in a few weeks i suppose.
wouldnt blame him, even so, its also not too far from 1.10, minecon is supposed to mark the release of Minecraft to the masses, and the general completion of minecraft itself. But i get the feeling 1.9 will be the last non-convertable version available, because im sure people are tired of losing their stuff, then again, for all we know, Joe could release the map this time without any conflict with the server