Paris Bike Scheme - je l'aime

I had a few hours to kill in Paris recently and was blown away by their new bike scheme. I wandered into a rank of them near the Gare du Nord and found someone to take me gently through the process of logging in - because I enjoyed the chat. It is easy enough and involves you giving your credit card details so the system can dock 150 euros as a deposit. It then tells you which bike to take, and off you go. They are sturdy, 3-geared and slightly eccentric-looking but work perfectly. It is hard to suppress a grin as you pedal past the stuck traffic and down your separated bike lane. I followed the Canal St Martin and when I needed a coffee I just found another bike-rank and slotted my bike back into the sturdy post rooted to the pavement. As I had only spent 20 minutes I was not charged anything. After coffee there was another bike available there and I pedalled back to the station, paying 10 euros this time. Luckily there was space in the bike rack and I walked away to catch the train. Had there been no space I would have had to find another nearby rack, or even leave the bike and forfeit the 150 euros. What a brilliant system. And apparently Paris is expanding it as I write. Nobody, other than the cognoscenti, thought the Parisians would take to it. Would Londoners? Bristolians?