I have a bit of personal perspective on this. My sister and her husband teach at the American University in Cairo. They were with me for the holidays, and they returned last Tuesday.
The day they left, we had been hearing about a few student protests. That was the extent of it. We were heartened by the departure of the Ali government in Tunisia, and while we suspected this to be the spark of the rallies in Cairo, nobody expected the situation to erupt with such swiftness or power.
By Thursday, the internet was shut down, as were the cellular phone networks. We had communicated by VoIP, and that link was now severed. I was left to wonder and worry as activism turned to unrest, then to violence. Historical patterns like this never bode well.