This just does not ring true, I am sure they mean the city centre (London and it's outer districts is a huge area)it would be a very large drain on what is already a very tight budget to blanket the city with repeaters for WiFi, The British government is in a financial mess at the moment, with austerity measures coming in, there may even be large cuts to the Olympic money set aside. Somehow this all seems like wishful thinking on Boris Johnson's part, he is a bit of an eccentric character to b e fair.
Also I am British, and quite proud of it but how can anyone say "London is the home of technological innovation." I mean seriously come on, Silicon Vally is the home of Technology, closely followed by far eastern countries like Japan and Taiwan