Compositor as Datablock

Is it possible to define compositor-nodes as datablocks as well?

It works well for shaders and environment settings.

If you could handle the compositor Nodetree as a datablock (just like shaders) you could:

1. Append / Transfer them to other / new scenes.

2. Switch between multiple postproductions / renderelements for complex setups.

3. Have a dedicated postproduction "master" and just link up the postproduction (would require to access output path).

Thanks - P