Blender Git Loki

Shape Keys now can be controlled with Vertex Weight groups as well!

Just fill in the name of a Vertex group in the Shape Panel, and this
Shape will then become blended with the reference Shape.

It is useful for example for a symmetrical modeled head, make a
copy of that Shape, and use two Vertex Groups to make it asymetric.
Of course the Shapes update nicely while Weight Painting.

Also new; since the Vertex group names reside on Object level, you might
want to copy these names to the other Objects that have the same Mesh.
That's a new button "Copy to Linked" in the first Edit Panel.