Until today watching the Central Park South Hawks nesting from the street has been like watching paint dry. 

5:45 p,m - Empty Nest.

5:47 p.m. A light colored head appears.  What's Junior (the male) doing on the nest?

6:00-6:15 p.m. After some movement around the nest he looks like he's trying to cool off a bit.  Not your typical egg sitting behavior. 

6:15 p.m. Charlotte returns with a gray squirrel.  Unusual behavior, since Junior has spent the last month feeding her.

6:17 Junior leaves the nest.

6:18 He quickly returns.  Charlotte is in the back of the nest out of sight.

6:23  After both disappearing to the back of the nest, they both reappear.  Junior then takes off for the evening.

6:30-7:00 p.m. Charlotte spends a lot of time out of sight, but also spends a lot of time at the edge of nest.

7:40 She settles down for the evening.

All of these behavior changes could be a sign that the eggs have hatched or are about to.  We'll know the answer in a few days.

Update: I received an email from Ben Cacace who was digiscoping (using a digital camera with a telescope) from a nearby hotel at the same time I was photographing from the street.  From the higher view, there appeared to be an egg in the nest.  So, we'll need to wait a bit before passing out the cigars.