Best mass transit system in the world?

Vox points to a regional system in Germany, Verkehrsverbund Rhein-Ruhr,

The real hub of the Germany economy is a lesser-known but more interesting urban phenomenon — the polycentric metropolitan area known as Rhine-Ruhr, stretching from Dusseldorf and Cologne in the north to Bonn in the south. None of the constituent cities of Rhine-Ruhr are especially large, but together they make a metropolitan area that's 11 million strong and hosts 26 of Germany's 50 largest companies. Knitting it all together and making it all work is the complicated but efficient Verkehrsverbund Rhein-Ruhr, the region's mass transit system. It's composed of 29 regional rail lines, 11 S-Bahn lines, 19 light rail lines, 45 streetcars, and over 900 bus routes.

Far too often we look at mass transit only in terms of its mobility improvement dimension. The more important dimension though may be its role as an instrument of shaping urban growth. As with, Rhein-Ruhr, efficient mass transit has been the critical contributor to the success of economically and socially vibrant metropolitan areas like Tokyo, Hong Kong, Singapore, Copenhagen, and Stockholm.