Airbnb has 23,000 residences listed in Britain

"Britain’s bed and breakfast and hotel operators are calling for the authorities to create a level playing field on safety regulations and inspections amid intense competition from people renting spare rooms on the cheap via the website Airbnb.
The site founded in 2008 has 23,000 residences listed in Britain, offering spare rooms or whole flats to tourists looking for alternatives to hotels. The American website’s parent company was valued at an estimated $10 billion by a recent fundraising, which makes it more valuable than Intercontinental Group, the world's biggest operator by number of rooms."
Source:  The Times, 19th April 2014
Note - It also said that the average UK host makes £3,000 in revenue from Airbnb, but I couldn't c&p that bit because it's behind the paywall