This week, I’m all about pushing the envelope and breaking new ground. So here’s an entire podcast about the Tube.

First up, the clever bit. One time CityMetric James O’Malley has since blossomed into the editor of Gizmodo UK. Earlier this year, he caused a bit of a splash with his scoop about how Transport for London has been using wifi data to track passengers – to find out how people actually move around London Underground.

So – what are TfL playing at? How will this sort of thing help transport authorities redesign their networks? Should we be worried? And are all the signs at King’s Cross such lies?

Then, the less clever bit: I’m joined by Stephen Bush so we can slug it out to debate the official CityMetric ranking of the London Underground lines. This was meant to be a short, jokey segment to end on. Reader, it did not turn out that way. Apart from anything else, it takes us a surprisingly long time to agree on what counts as a line.

Before we go, a spot of housekeeping. This is our 48th podcast. For number 50, Stephanie has kindly agreed to come back, and in a change from our regular format, we want you lot to ask us things. If you have any burning questions, you can tweet us at @jonnelledge and @stephanieboland.

The episode itself is below. You can subscribe to the podcast on AcastiTunes, or RSS. Enjoy.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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