I think Bump Mapping could be added in a week or so... It's really not that hard: Like it was said before, you just have to load the shader file, create a shader program from it, switch the resulting shader on and pass some arguments... And shader code for bump mapping can be found all over the net.
But for me personally LFS looks good enough for now, I just like to see a bit more detailed cockpits... Nicer lighting (bump mapping, specular mapping and HDR) can wait.
Maybe Scaven just isn't so much into graphics programming so that he doesn't bother to learn shaders, and that's perfectly fine for me...