Tim Berners-Lee on Scientific American:
In contrast, not using open standards creates closed worlds. Appleâ€™s iTunes system, for example, identifies songs and videos using URIs that are open. But instead of â€œhttp:â€ the addresses begin with â€œitunes:,â€ which is proprietary. You can access an â€œitunes:â€ link only using Appleâ€™s proprietary iTunes program. You canâ€™t make a link to any information in the iTunes worldâ€”a song or information about a band. You canâ€™t send that link to someone else to see. You are no longer on the Web. The iTunes world is centralized and walled off. You are trapped in a single store, rather than being on the open marketplace. For all the storeâ€™s wonderful features, its evolution is limited to what one company thinks up.
I don’t think we can categorize iTunes as being part of the world wide web; it isn’t. The iTunes Music Store is a store that has some similarities to the Internet in how you access information within, like “itunes:.”
FarmVille is an online game and has 80 million users. Can you make a link to any information in the FarmVille world? That would certainly be interesting but it’s another thing to point fingers at FarmVille and say that it isn’t using open standards just because you can’t link to information within the game and that it’s evolution is limited. FarmVille runs on Facebook and it is even bigger. Should we be able to make a link to any information in the Facebook world? Again, cool idea, but…