Many of the top ten cities have city-wide bike sharing systems. And the majority of them are in Europe.
"Bicycles have numerous benefits, but it takes a serious commitment to city planning to make those benefits practical. Cities like Paris, while trying to be bicycle-friendly with programs like Velib', remain too large and frenetic to be considered truly bicycle-friendly.
While it seems like America is just taking heed of this recent resurgence in bicycle culture, other urban areas the world over have long been ridiculously bicycle-friendly cities through their urban planning."