The main objective of the system is to supply an increased choice in your mode of transport traveling around Hammersmith and Fulham...This looks like a brilliant idea. I think it might work better in a tourist capacity or tourist town like Put-in-bay Island (OH), or Cape Cod, or the Florida Keys, or Hawaii that already rent a lot of bikes, but the availability of inexpensive bikes and cheap electronic gadgetry for electronic locking systems might make this a go. I hope it's successful so I can start one in Chicago. In fact there are some great bike rental places in and around Navy Pier and downtown Chicago for taking rides on Chicago's famed lake front bike-path.
A few other thoughts though, you need to pre-signup. Pre-signups are the ban of simple convenient pay systems. For example pre-signups are the ban of internet wireless services such as that of TMobile / Starbucks service. Why not just put the 1800 number on the bike and let people call in and use a credit card. After that they just give their name and security code and go.
Second, To go a little further; with todays cheap WAP interfaces and wireless devices you could simply create an interface in which you just type in a username and password and it automatically unlocks the bike and charges your card. Think of it as an e-commerce system built into a cell phone / lock built for the sole purpose of buying bike time. No phone calls or human interaction necessary. This leaves the 800 number people and staff to simply offer support, keep track of and maintain the bikes and electronics. I think I could almost build a cellular enabled lock system myself with a couple hundred dollars. A mass produced unit would be even cheaper.
BBC NEWS | Technology | Phones power bike rental scheme
The most interesting article I have found is and an post including correspondence on a local UK cyclist club website at htcycliests.org. It explores a plethora of issues and is fascinating. Read the full report it is truly fascinating.