HTMLbars will land well before 2.0, most likely in the next release. We've been doing the integration piecemeal to ensure that we don't break production apps; we want everyone to get to experience the new awesome.
Also, some of the points in the RFC are features that depend on the new templating engine but will likely not land in 1.10. We give guesstimates for when we think things will land in the RFC :)