So, it's nice to see that Microsoft have now offloaded the product to Phase One, makers of the excellent RAW conversion software, Capture One.
I never actually got around to trying the free upgrade to Expression Media, but perhaps now I have reason to do so. Hopefully some decent integration with Capture One is on the way. At the very least, getting Capture One to properly preserve IPTC data would be good. Some speed on viewing RAW files in Expression Media would also be nice.