The conventional wisdom about Iraq is that we are seeing more and more casualties. Why is this the conventional wisdom? Well because reporters aren't generally good at math.
Donald Sensing led me to this Belmont Club analysis. Long story short, the deaths this year have been almost identical to the deaths last year. Casualties this year (including wounded) are actually significantly lower, ~30% less. The news gets better when you look at numbers for the last three months. Then deaths drop by 20% and total casualties are down by 50%.
Well golly gee that's not what I though was happening. In short, the conventional wisdom is actually conventionally folly.
UPDATE: If you don't believe me this site has very complete casualty records, including a good summary chart. After some analysis of the numbers, it appears casualties peaked around the time of the Iraqi elections last year and have been declining since.