San Francisco is the New North Pole

The Mercator Projection works very well with interactive maps. This is why most online maps use some form of Spherical Mercator Projection.

The problems with the Mercator Projection are well known. The projection distorts the scale of areas along the lines of longitude. Therefore areas close to the poles seem far bigger than areas close to the equator. Which is why Greenland on maps often seems to be about the same size as Africa (it isn't).

Another problem with the Spherical Mercator Projections is that you can't actually show the poles because the Mercator Projection projects them at infinity.

Mercator Extreme is a fascinating experiment which allows you to set any location on Earth as the North Pole and visualize the resulting Mercator Projection distortion created as an interactive map. Type in your address into the map and you can visualize what a Mercator Projection map of the world would like if your home was the North Pole.