Gary - works fine here without a key. Maybe it depends on your IP which is treated differently by Google for some reason.
Anyway, obtaining an API key and setting it is a matter of minutes, and would probably solve your problem.
Hi Zohar, thanks for sharing this wonderful piece of code. I have a query, I'm trying to plot data points which are mapped on to corresponding co-ordinates. The problem is, the number of data points are large (around 15000 - 35000 points). I'm able to plot these data points on the map, but facing issues in zooming/panning speed. The map reaction becomes too slow whenever I try to zoom in or out with the data points on the map. Is there any limitations in the number of points on the map or should I check for any other parameter to overcome this issue.. Thanks