There are pick-up/drop-off stations everywhere and the bikes all seemed consistently in good shape. It costs £2 for 24 hours. This allows one to pick up and drop off a bike as often as you like. As long as each individual ride is under 30 minutes there are no more fees. Annoyingly, while rides longer than 30 minutes incur additional charges, they fail to indicate the fee.
There was a station directly in front of my hotel and from there I headed to Buckingham Palace:
It was a mild January evening but I was impressed at how many cyclists I saw. A nice bike path in Hyde Park:
A few more photos:
Yes, I had a lot of fun: