I would recommend checking out Tom Coates' "Web of Data" talk. Presentation: http://www.plasticbag.org/files/native/ http://www.plasticbag.org/files/native/ Aud

I would recommend checking out Tom Coates' "Web of Data" talk. Presentation: http://www.plasticbag.org/files/native/ http://www.plasticbag.org/files/native/ Audio: http://www.webuser.co.uk/carsonworkshops/TomCoates.mp3 http://www.webuser.co.uk/carsonworkshops/TomCoates.mp3 It explains that the data is the web site (app), or at least the most important part of it. By building a web app on top of an API you are immediately exposing the unique and interesting part of your service, the data. This leaves you, or anyone else, free to build whatever interface on top of that data. At Yahoo we absolutely use our own APIs internally to build our sites. That means most of the APIs we make publicly available are the ones our own developers have been using.