What is so exciting about XLink? As with all the technologies presented by World Wide Web Consortium (W3C) they have aimed to make XLink scalable.
Imagine a document about birds published in swedish. I could create a link from the name of one of the birds to a dictionary on another website. A link created with XLink can have many destinations so a websurfer could find out what the bird is called in german, spanish, swahili or maybe even english. It all depends on what dictionaries I, the publisher, have made a link to.
If I find a new dictionary, a swedish - turkish dictionary, I can add that dictionary's address to my "birdlink" and voila, turks can find out what the bird is called in their language. Actually...anyone can find out what the bird is called in turkish. Scalability:)
Another example. A document about communism has links to webpages that criticize communism. In this case scalability could be quantitative; more links to documents that criticize communism, or qualitative; links to pages that don't criticize communism. And when communism falls in your country you can start making links to documents that criticize capitalism instead. It's only a question of scalability.
From no links...to one link...to many links. From here to infinity!

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