Probably most of the credit goes to the people involved in the project and their ability to champion their cause and provide these services, straightforward documentation that looks like it's written for humans by humans, etc.<p>Another part of it might be that BART has been highly automated and computerized since its design and inception so the data they offer has been available in some machine format or another for a long time. I remember there were a couple Macs with atrocious screen burn-in displaying all sorts of real-time info from the inside of the Berkeley Shattuck Ave Station Agent's fish-bowl in the early 90s - if you could hook it up to a Mac then, it seems natural you can offer it over the Web today.