Emberjs-addons are ports of the old sproutcore ecosystem. They are not changed, and it seems that they do not get much attention from the main emberjs team. They concentrate on the new "emberjs-data". However, the old data warehouse is proven, and the modified version works fine with the current version of emberjs (0.9.3).
In contrast, while the rewritten version looks very good, readme projects explicitly state that it is not yet considered "ready for production."
Which one to choose? In my opinion, it depends on your project. If you are looking for something stable or want to host your application in the near future, I would give the βoldβ scroll punch. On the other hand, if you are just starting out with your project, use the new and shiny "emberjs-data", but be careful that you have to fight some edges.
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