I might annoy people here as well.
Firstly - he did also say he would honour it till the end of the initial proposed scheme so i don't think it will end straight away. And if I remember rightly then bus fares are fairly cheap anyway. A 7 day pass is £13 so you can pretty much go where you like for less than £2 a day. Although I haven't lived in London for 5 years so excuse me if this info is incorrect.
Secondly - he also said that he didn't see why one of the richest western cities should be subsidised on the backs of people in one of the poorest cities. if we want their oil we should pay for it - and I agree with this.
If we relied on one particular export for the majority of our GDP and the gov't accepted reduced prices which meant that a vast majority of the population lived in extreme poverty then we would be furious and would, rightly, feel like we were being ripped off. We in the West rely too much on cheap labour/products from others who are suffering to provide us with day to day things that they themselves cannot afford. We need to start looking at the whole global market/economy and make some serious changes. And yes that does mean that, certainly for a while at least, we may be a little bit worse off. But things cannot continue in the way they are. I believe we are heading for a global crash and we are too blind to see it and too apathetic to do anything about it. It is still a case of, "well I'm alright, sod the rest".
Sorry for the rant and I know I have oversimplified the issues somewhat and gone a bit off subject!

It's a bit of a soapbox issue for me.