An interesting short video about how UCL Engineering School is using the data from the Oyster Card system to map out how Londoners use the network. The obvious benefit is that TFL could better invest in problem locations to relieve congestion. The main takeaway is that London is a network of polycentres - meaning there is no one central hub - but a collection of them.
To be honest I'm not sure why the data hasn't been looked at before. About 3 months ago, I got letter from TFL asking me to record my complete journey history using a pen and paper form. It seemed insanely inefficient and I didn't bother to complete it. At the time I thought why don't they just use the information from Oyster Card system, glad to see they now are.
You can learn more about the project from Oyster Give Up It's Pearls page from the UCL Engineering School.