Howdy neighbor: I live in NYC too. A lot of NYC already does have fiber in the form of FiOS. I'll also observe that NYC's overall Internet situation appears to be much better than many places; right now I'm paying $50 a month for 50 Mbs down / 5 Mbs up through RCN. In Tucson, where I used to live, I was paying $70 for 12 down / 1 or 2 up.
Google is presumably targeting the places with the crappiest service and the most amenable local governments; NYC's service isn't terrible and its government isn't exactly known for being responsive.