Hi,
I noticed that one of the SoC'ers is working on integrating libpoppler with Inkscape for PDF import - I have investigated this briefly and written a quick-and-actually-not-too-dirty PDF to SVG converter with libpoppler and cairo. It is available at http://seis.bris.ac.uk/~db9052/pdf2svg.tgz.
It is a *very* simple program that opens a PDF file with poppler and renders it to a cairo surface that is connected to an SVG file. Very simple and very effective and you might want to think about integrating it with Inkscape as is. It has worked on everything I've tried it on, though it has the nasty habbit of slicing large bitmaps up into small chunks. It doesn't produce the most streamlined SVG files either...
Try it out and let me know.
Dave