Space.com featuon space habitats

Nice Space.com feature on space habitats, with a link to a gallery of all of the old 1970s illustrations: http://www.space.com/22229-space-station-colony-futuristic-technology.html?cmpid=532471 Someone is commenting that saying such things are possible in a millennium is wrong. Less sure about Elysium, but the NASA designs theyre decorating this article with can be built in much less than a century.
Regards, Mike Combs