One other thing about those Johns Hopkins figures. In 2002 the CIA estimated Iraq's population at 24m (July '02). Today the CIA estimates that Iraq's population at 26.7m (July '06). If the Hopkins figures are an accurate representation of the Iraqi population (1474 births, 629 deaths, 12801 people over 4.5 years), then the overall population growth should have been around 1.4m (total population 25.4m), which would leave Iraq's population well below the CIA's July '06 estimate of 26.7m. Even stranger is the Hopkins study includes an estimate of 26.1m (not sure as of when) for the total population, which is well above where projections using their statistics should have had it.
{Please check my figures. I could have missed something as I've sort of rushed these calculations.)