New York City Real Estate - Stagnant?

Just spoke to my mother, who is a pretty successful real estate broker who specializes in townhouse sales in New York City. She and her partner work mostly on the listing side of the equation and they currently have four townhouses and multi-family buildings in their inventory. The interesting thing is that they are not really seeing much action on these buildings. Located in very good neighborhoods, the lack of activity is an interesting development at the very least...especially with the recent economic data we have seen. Is this a temporary glitch, or is something bigger at work here?