Reports from an outbound crewchange saying two trucks with jet engines on the back are currently working on the taxiways.
Rumor control says there may have been a disagreement as to whose responsibility keeping the runway and taxiways clear of ice was.
http://atyraunews.com/2007/12/10/zaneslo.html
(In Russian).
That AMS GUW flight was further delayed till approx 0830am local this morning.