[pitnips]

It's a localized network effect only if they are isolated to local areas. However, most people in the U.S. (especially outside of SF) only have Uber, so the network effect grows stronger as consumers only need one app regardless of the city they are in.

I'm not sure I understand your yellow cab comparison. With Uber, no one needs an understanding of the local markets (aside from the laws, which can be done at the corporate level). Uber just shows local drivers how to make money, and they take a cut because they have a strong technology, brand, and user base.

As far as international expansion, I agree it would be much tougher. But even if they aren't successful outside of the U.S. (which I still think they will be), they will cash in billions.