Hey guys, sorry for the late reply, went camping with the family over Easter, came back tired, lots of downtime.
Here's a quick
photoshop mockup I did of the layout and basic idea.

Edit: my friend kindly added a sphere to the 3d preview :P
Down the left side is a hierarchy of materials, techniques and passes, which you can create from scratch or load from a .material file.
Selecting a material, technique or pass will bring up all it's properties in the area to the right.
If a pass uses the programmable pipeline, you can either select an existing vertex/fragment program, or create a new shader using the node based shader builder.
I'm working on my application now, I'm pretty confident I can create a useful tool in the given time frame, and I would love to continue working on and supporting the tool after GSoC.
A bit about myself: I have experience with c++, wxWidgets, Ogre, directX, hlsl (cg and glsl versions would come after GSoC), and a good understanding of Ogre's material framework.
I guess you could say I have some experience with open source projects (I ported
Box2D from c++ to ActionSctipt 3, which I believe sinbad used when trying out Flash :P).
I am very passionate about real-time rendering and engine programming, and a material editor is something I would
really love to do, this is my only GSoC application.
I'm not really interested in writing an exporter/converter, so if the mentors think my proposal is too ambitious, then I'll just be content with what I've learned researching and thinking about this over the last week and go do some labouring work instead. (:
All the best,
-Matt