I have a good friend who has a very successful rapid prototyping business; I've watched this technology explode in the last 15 years from close up. All indications are that the migration from high-end, B2B applications, towards consumer oriented applications, is in full swing. IMO it is identical to what happened with print technology in the 80s. Everybody in the industry is talking about it, the smart guys (like my friend) are working to reshape their businesses to be in position to take advantage.
I agree with everything Rizzo says above; it's still a bit out of reach, certainly for the mainstream modeler. But make no mistake, it is coming and will impact our hobby. I think the first thing we'll see is more accessible services (software, prices, customer service) followed later by truly useful affordable equipment.