The Economist published an in-depth and thought-provoking article a week ago:
"MOORE’S LAW—the prediction made in 1965 by Gordon Moore, that the number of transistors on a chip of given size would double every two years—has had a good innings." However, the transistors "have already shrunk to a size where every atom counts. Too few atoms can cause their insulation to break down, or allow current to leak to places it is not supposed to be because of a phenomenon called quantum tunnelling, in which electrons vanish spontaneously and reappear elsewhere. Too many atoms of the wrong sort, though, can be equally bad, interfering with a transistor’s conductivity. Engineers are therefore endeavouring to redesign transistors yet again, so that Dr Moore’s prediction can remain true a little longer."