Scoble writes about how smart displays have failed. The scenario he describes could be pretty compelling:
What was a Smart Display? An LCD panel that would display images from a high-power server. Interesting idea, if the cost were, say, $300 each (instead of $1000). Imagine having a server in your closet with, say, a dozen panels, instead of a single Tablet PC. You could display pictures on one. Recipes on another. Have your son playing a video game on another. Your daughter doing homework on yet another. All hooked to a server via WiFi.
However the cost of the Smart Displays is not the fundamental problem with this scenario: you can only connect one Smart Display to a host machine running XP and, to make things worse, when that display is being used the screen attached to the host machine can't be used. Presumably there aren't any fundamental technical issues with this and it's just a matter of Microsoft wanting people to buy more XP licences. For the 4 person family to each use a Smart Display concurrently, they would need to buy 4 PC's and 4 Smart Displays instead of 1 PC and 4 Smart Displays.