Reuters just published a poll of primary dealers, post FOMC. Five of 17 expect Treasury buys and 10 of 17 forecast MBS purchases.
My own feeling is that QE3 will probably happen (eventually) but that it won’t have much effect. What the Fed was saying today was that it’s watching Europe and that it expects the US economy to grow modestly. If either of those two things go badly, the trade is to buy USD not sell.