Well between this, the potential of a super eruption in Yellowstone, and the risk of a large rock or comet hitting the earth, not to mention all the other possible major calamities its a wonder I get out of bed in the morning.
As far as I am aware the science behind this is valid and if it did happen at the wrong moment the effects could be catastrophic (our societies are almost entirely dependent on electricity as mentioned in the article). As such I see no reason not to take appropriate precautions to defend against such a possibility.
Great thing though is channels like Discovery are making a mint by making special "documentaries" about such stuff and what could "happen".