I think pre 1.0 should represent that breaking changes are happening more often.. a 3-month release cycle with breaking changes in pretty much every stable release doesn't bode well in that regard. However, they have been very responsive to the larger community and these additions and changes are really a good thing. Mostly they break out rendering pipelines to support multiple renderers, and they reduce opportunities for mutations, which fly in the face of a flux-like workflow.
