Recommended reading
R.L.G., "A language with too many armies and navies?", The Economist 6/21/2013. This post gives a laudably concrete discussion of the differences among contemporary regional varieties of Arabic, with examples taken from the r/Arabs Dialect Project. It also quotes from a 1998 paper by my colleague Mohamed Maamouri, "Language Education and Human Development: Arabic diglossia and its impact on the quality of education in the Arab region" (Discussion paper prepared for The World Bank Mediterranean Development Forum, Marrakech, 3-6 September 1998).
