Michael Novak has an interesting column in National Review online, where he gives the following data:
From March 19 to April 30 (42 days) there were 112 U.S. combat deaths, and 29 noncombat deaths in Iraq.
From May 1 to August 26 (118 days) there were 63 combat deaths, and 78 noncombat deaths.
So if one looks exclusively at combat deaths, in the first 42 days there were approximately 2.7 deaths per day. In the next 118 days, there were approximately 0.5 combat deaths per day...or 1 combat death every 2 days.
Now, every death--combat or not--is very unfortunate. But if we compare Iraq to Vietnam, or even Korea, it's pretty hard to see where the word "quagmire" comes from.