Can cycles material node info be saved for reuse in other projects? In a similar way to how you can import brushes for sculpting, can this material be saved in a way that it can be imported into a different project and applied to one or more objects?
Appending the material data is the only way I can think of doing it currently.
Appending the material data is the only out-of-the-box way to do this AFAIK. To organize a "material library" for yourself, you could save your select materials to a "materials.blend" file somewhere easily accessible on your hard drive. Then you can always append them from that same "library" file whenever you need.
Alternatively, here's an addon that will facilitate you generating your own asset libraries (for materials, models, textures, light setups, etc)