While New Yorkers battle over the new-fangled bike shares (new for New York -- they've been implemented in a lot of major cities here and abroad) and their corporate sponsorship, the Canadian economics blog with the sexy name Worthwhile Canadian Initiative (oh, that understated Canuck humor) wrote up a review of bike share claims here.
WCI's Wooley concludes that bike shares don't have much impact on health (bike sharers are mostly youngerish and already physically active), pollution or congestion, and doubts it's good for tourism (tourists are not comfortable biking in unfamiliar traffic and street patterns), but it could ease overloaded public transport since public riders are the most likely bicycle-share candidates and bikes get places faster than public transit.
The conclusion is a bit of understated humor itself. Users support bike sharing because they believe it will curb auto congestion and pollution; the mayor thinks fewer cars are better for tourists. No one is waving bike shares as a solution to public transit congestion, although it is mentioned in the NYC feasibility study.
So all this controversy was just another delay for the 2nd Avenue subway?