At a trade show last year, I asked a Linos (Rodenstock) representative about the differences. One thing mentioned was that a CCD sensor has a more reflective surface than film, so the coating on the rear element is different to account for that. He stated that their newest lenses would work fine with film, though he pointed out that the shorter focal lengths only cover a very small area.
My personal opinion is that unless you plan on getting a PhaseOne, Imacon, JenOptik or Leaf back, skip on these high priced lenses. While they might be better at larger aperture openings, I doubt the difference would be enough to matter for most images. Also, I have yet to see any convincing evidence that you could not use normal modern large format lenses with any of those backs. Comments on the ALPA website seem to confirm my opinion that many modern lenses are quite good for film or any other method of capturing an image.
Ciao!
Gordon
