They'll be back...
From what I understand they are still there. However, they are few in number so only accompany random international flights headed for or from a troublespot.
I heard reports that they will start putting Delta Force operators on the flights, for a while at least. I definitely wouldn't want to cause any trouble on a flight where there might be a plainclothes d-boy sitting down the aisle reading a newspaper. We will probably see a lot less air rage as a result too.
-Steve G.