Three nests in Manhattan have been confirmed to have brooding hawks so far this year, Washington Square Park, Tompkins Square Park and Fifth Avenue. This leaves a number of previous nest sites to check over the next few weeks: Inwood Hill Park, Randalls Island, St. John the Divine, 350 Central Park West, and 310 West 72nd Street. (I've heard good reports about activity at each nest except for Randalls Island and 310 West 72 Street but these are never closely watched.)
This leaves a large amount of northern Manhattan without known nests, including northern Riverside Park, High Bridge Park and Fort Tryon Park. Also, although the male died at 96th and Lexington and the nest was removed after the building was tagged with graffiti in the fall, may area residents have reported seeing hawks in the area. The CCNY nest on Shepard Hall lost the male just before nesting season last year, so it is possible that hawks will return to this nest too.
I doubt Manhattan only has eight nests this year. Let's hope we find the new ones soon!
So this is my preliminary guess at nests for this season and older sites that will need checking: