Oyster cards to be used on trains (BBC News)
 

Train passenger should be able to use their Oyster cards on most of the London rail network by the end of 2009.

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Good news, I must admit I like my Oyster. I even got one for my old mum who loves it as well due to its simplicity. Although its probably really because I am paying for her travel :D :eek:

Living in Paris, and using a "Pass Navigo" which looks much like the Oyster card, I use an Oyster every time I come to London. There is one great feature in your card system which is the "load it then pay as you go" system (which is linked with a rebate on the prices of tickets); we lack this function in Paris system.

Concerning SWT, have they declined the proposal for operational reasons (dealing with the crowd at Waterloo) or financial matters only? It's a pity such a major network does not join the system.