Have you been in contact with the OpenStreetMap guys. There's a thriving London community of mappers who I'm sure would be interested in talking to you. https://twitter.com/OSMlondon is probably the easiest way to get in contact.
Any idea why we got removed from the front page? We (the creators of ViziCities) didn't even post this to HN.
This is ridiculously good. I never realised the London underground was shaped like that!