ParaPundit has a very informative and clear essay (under the date "2003 April 3") on what we may expect our casualties to be when we go into Baghdad. Also note some thoughtful side issues, for example, why did Saddam allow the Republican Guard to be positioned so far out of Baghdad, how many paramilitary there are in the city, how difficult it is to even know the population of some of the cities we have taken, etc., (the links are useful). A very thoughtful read.