The data is from http://chriswhong.com/open-data/foil_nyc_taxi/ -- I pulled 10k random pickups from each day/time for the heatmaps.

I used http://leafletjs.com/ and https://github.com/Leaflet/Leaflet.heat for the visualization.

NYC has a open data policy. http://iquantny.tumblr.com/ has great analysis and commentary on a lot of the open NYC data that you might find interesting.