New York Mayor Bloomberg is in France, and apparently considering a bicycle rental program similar to the popular parisian Velib system. Bloomberg doesn’t sound very optimistic unfortunately. Apparently NYC tried this out on a much smaller scale earlier this year. Chicago and Portland are evaluating a rental systems too.

The velib system in paris is awesome. I was there last month.
It seems very well thought out. As far as I could tell the fleet is located entirely on or very near designated bike lanes or ped/bike trails (on the boulevards). There were lots of bikes, both in use and at the rental racks. I also saw Velib maintenance trucks driving around with wounded bikes. I know the system there is new, but they seem committed to keeping the bikes in good shape so they are available to use.