I think they'd have to work with strands much longer than the 1 meter ones currently available in order to make a sufficiently resilient "rope". Also, the article didn't mention it, but that 1 meter strand was probably made under strict laboratory conditions after a great deal of trial, and it's not likely able to scale up to manufacturing standards just yet.
Some issues come from phonon effects. These ropes would be a single crystal in effect. From thermal 'noise' you get phonons in the crystal. Since the crystal is a big tube, these phonons can only travel up, down, or create standing waves around the tube (essentially). When these phonons interact, there may be enough energy present to break the crystal/rope. This happens a lot since atoms are real small. Doping the crystal may help, but that'll weaken it. Cooling it may help, but that's costly. Much more basic research is needed.
