It wouldn't need to be node based, but simply a way to 'cook' 'bake' a set of attributes into one material. therefore
removing the need to blend materials which have more attributes than you need. As is demo'd in the video.
For example,
From a list you would add what you want then 'bake' / 'cook'.
add sss, spec, 2spec, textures, indirect, direct, reflection etc...
This material is now saved and can be used.
The difference being only the attributes you need are present.
This would also be awesome for brushes too.
The one thing which is annoying about materials and brushes is even though you can save them out, tweaking is more an exercise in going through seemingly endless attribute lists.
Its great to have that much customisation, but when you got what you want it makes sense to
reduce the screen clutter.
Hence
bake or cook material and brush.
Also being able to apply a texture as well as an adjustment curve to any material attribute is needed, if you really want shading in zbrush to be helpful.
...
To clarify, instead of plugging materials into materials, why not plug attributes into materials?
Its fine to have zbrush as a totally 'unique' app. Just means that for artists with access to other apps for rendering and texturing and most importantly concept and look development. Zbrush won't be used as widely outside of modeling which is still its strongest feature.
The die hard fans will cling on, but to be honest better and faster results can be acheived outside of zbrush with regard to rendering and texturing even if only for concepting. I dislike jumping from app to app which is why I think pixologic should look at how to upgrade the way materials are used, a 'less is more' approach.
Mainly how to utilise less attributes to create a look for your model, be it organic or hard surface. Once you start overloading the amount of 'tweaks' and 'attributes' you use to develop a look the harder and it becomes to translate, therefore becoming a waste of time.