Interesting. I'm in Montreal, the birthplace of Bixi, which runs the London bike share program, and the upcoming NYC program as well as many others. Works fairly well, but apart from the cost the docking stations cost the city parking revenue.
One major administrative cost is moving bikes around. People tend to take them downtown during the day, and out of the town at night. Even if you don't need docks, you still have to move bikes.
Definitely true. Redistribution is always a hurdle, though with viaCycle's realtime data, we can do some very cool things with incentives and pricing to help the system balance itself.
Bixi takes a lot of parking spots partly because finding space for large stations is difficult. By using existing bike racks, we can often put in bikes without modifying anything. Plus, although parking is lucrative, replacing room for one car with 10 bikes that 100 people can use is a good trade in our book.
We do take payment info on signup. Right now programs are localized so we set up different websites for each, but we hope to link everything together in the future. You can see an example at http://gt.viacycle.com
Does that actually work to balance out demand enough? I know Paris tried to do the same thing but found that incentives weren't enough. Then again, that was the city government, so they may have been more constrained in terms of how large the incentives can be than you.
Incentives wouldn't have to solve the problem totally. As long as they made some users happy and redistributed some bikes, incentives would help reduce costs.
One major administrative cost is moving bikes around. People tend to take them downtown during the day, and out of the town at night. Even if you don't need docks, you still have to move bikes.