New Sync has been development for about a quarter. Right now all effort on the Sync project is to get the basic workflows finished and testing the various Sync clients (Fx Desktop/Fx Android).
The team is looking to have a more understandable self deployment strategy by the time this ships in Firefox release ~12 weeks. This is not a promise though. Engineering work is tricky to estimate.
And I hope they will implement it on Firefox OS very soon, otherwise the whole syncing is not really that interesting.