You read it here first.
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So what does this mean for Away3D, if anything?

Nothing really. The concurrency features could potentially be used for parsing large files, but the problem is that the way they are constructed makes them not very suitable for use in a third party library like Away3D. It would require too much work on the user’s side (i.e. you.)

Using workers for the parsers would also limit users to the 11.4 player, since it’s not backwards compatible.

I am thinking about a backwards compatible, simpler way of at least enabling background parsing in the loading framework, even if it would not come as a default feature, but one that could be used with as little hassle as possible.