I've already been called by reporters asking my impression of how well the warning system worked for Moore. As far as I can tell (this is preliminary), it worked well.
Here is the watch:
I don't know the exact moment the warning was issued, but it was posted on my blog at 2:46pm. That means there was at least 34 minutes of warning for Moore. The national average is twelve.
The NWS had the tornado warning out 16 minutes before the tornado ever touched the ground (see map below and radar loop, purple link).
I listened to an OKC radio station, KTOK, and they were in wall-to-wall coverage long before the tornado arrived. My ex-television station KFOR TV was on national television and they did their usual great job! The background audio of live reports carried the sound of the sirens.
In addition, the enhanced tools of meteorology like debris balls, "tornado debris signatures," and wind velocity centers pointed to the exact path of the storm. These were provided to enhance the meteorological certainty to people in the storm's path. If you would like to see a high-definition time lapse of all of this on radar, please click here.
So, it looks like weather science did its job.
Based on preliminary reports, the death toll may be high. A comment: Having lived in the area I can state that virtually none of the homes have basements. This tornado will almost certainly be rated F-5. Unless you are underground or in an reinforced safe room, those in the path of the F-5 winds can be killed in spite of the warnings as a closet does not provide enough protection when a home is flattened. This tornado was so strong, debris from Moore is currently falling (8pm) on Branson, Missouri.
ADDITION: Just after I finished this posting, multiple news organizations have reported the Oklahoma Medical Examiner says
Here is a more precise map of the path.
The Atlantic has an excellent backgrounder on tornadoes.