Sassan,
I remember refusing to buy into the computer age until they got to 6gig hard drive. In todays money that's 312 NEFs ( Nikon RAW file ). When that finally happened it was for me the bees knees. Two years later I got another at 30gigs. Now I have 300gigs, quite unimaginable a few years ago.
Similarly with digital cameras and the cost of them. I am sure as chip manufacturing technology improves and gets cheaper there will be a market for cameras supporting this level of mp, after all Hassleblad currently has the H2D at 39mp. Phase One also do a 39mp digital back for it, the P45 ( £18k to £20k depending on version and excluding VAT ). So a limited market yes, but a market all the same. Despite those digital backs Sinar still makes and sells the P2 in 10" x 8" for those that regard 39mp as not enough.
I watched a local tv program a few weeks ago, and among various artists it featured a commercial photographer who would not use anything smaller than 10" x 8". If my memory serves correctly he said a single sheet of film and processing was £25 per shot.
Don