An event to unite the capital

The arrival of the full Oyster card service across London is a big event - something almost everyone will welcome.

Mayor Boris Johnson has understandably described the length of time taken to finalise the details of the deal with the train operating companies as "aeons".

He and his predecessor Ken Livingstone have had to overcome the obstructiveness of a number of rail operators.

With the full "Oysterisation" of the capital there will be a new map which, in time, may come to affect the way Londoners understand their city.With luck, it will tie south London more closely into the Tube-dominated north.

Oyster has been a huge success. It has made travel easier, reduced costs and demonstrates how technology can work to improve daily life.

Londoners must hope that during the public expenditure bloodbath that lies ahead, decent services can be maintained. But for now, welcome to Oysterland.

* Tony Travers is the Director of Greater London Group at the LSE.