Since recently we have an OBJ importer in form of an extension. IIRC
there was a debate how this extension should be implemented better
(real importer vs. extension). So, I've just stumbled upon
-- Open Asset Import Library, which is
designed to help importing various 3D scene files into applications.
It covers not just Obj, but also 15 more file formats, including 3D
Max and the like. Could be a good GSoC2009 project for somebody,
especially if importing would come with live preview :)