Seems like "virtual" is perhaps the wrong way to label the posting and is being miss-used in the title, they are really multi-station or multi-seat desktops. Up to ten monitors and keyboards per PC. No Server Required. In fact many of the schools are in remote rural locations: http://www2.userful.com/company/linux-desktop-virtualization

Looks (from the press release) http://www2.userful.com/company/linux-desktop-virtualization like 18,000 seats have already been deployed and are running well. And the budget has already been allocated and system vendors have won the auctions to supply the hardware.