I just got back also - it was extremely interesting. I counted 43 attendees, many of whom were not regular Subtalkers, but just happened to hear about the trip and decided to attend.
Of course, the highlight of the tour was walking through the abandoned tunnel and on the old platforms of the Sedgewick Ave and Anderson/Jerome stations.
Thanks to one of the attendees, whose name I didn't get, we also got to see an old staircase which lead to the Polo Grounds - the last suviving part of that building's history.
Thanks again to everyone who helped make the tour most enjoyable and educational.