You've got to figure there are lots of calls being made because of the emergency. The fact that it doesn't roll over into voicemail, is probably a sign that the system just isn't working because of the volume of calls.
Actually I am finding the cell system not working again, very interesting. It was reported here over the weekend that the cells went down at the Sooners game right after the bomb went off. At the game, it had nothing to do with panic...interesting.
Advantages of taking the cell systems down, no secondary explosions, no communication between t-cell members...cell phones are used frequently to set off IEDs.