It's a trippy idea, and, believe it or not, a really old idea. I think it was either Asimov or Clarke who first came up with the idea over 50 years ago. The REALLY eerie part of it, though, is that whichever guy came up with the idea actually used carbon as the construction material for the cable. The reason they're looking at the carbon nanotubes as a construction material is that there isn't a material in production today that wouldn't snap under its own weight with a cable of that length.
Can they do it? I vote yes. Will I live to see one? I doubt it. I think the article covers it best. I think our society has become too fickle to fund something like this over the time span that it would require. That's why we have a zillion miles of empty underground tunnels that were supposed to be the world's largest particle accelerator (in Texas?).
