Take some time to listen to the ATC tapes.
Not just the small segment in question but 30 mins before and an hour after.
Lots of de-iceing going on. In fact delivery at one point delivered one aircraft who replied "not going to push back yet as the queue for de-ice is 45 mins"
(not the exact words.....)
Several thousand gallons of expensive de-icer was sprayed around that night.
Every other aircraft was de-iceing, listen to the audio!!!
http://archive-server.liveatc.net/kb...2007-2330Z.mp3