More seriously, it has been gaining popularity because of it's direct relationship to built-in structures in most programming languages.
For example: XML doesn't have a concept of arrays, but accomplishes storing collections in it's own special way. It's up to the parser to determine how this should be referenced and interacted-with, while with JSON there's no question: it's an array.
UPDATE 2013-04-08: I got a phone call from a recorded voice that said that my laptop have been shipped and I would get it in 24h.
UPDATE 2013-04-09: I got another phone call from the Dell support center that confirmed the shipment but they said that may laptop have not been fixed. They are shipping it as it was a month ago!
They are sending me a new laptop in about 2 weeks and in the meanwhile I can keep my old one. I asked if they were sending me some sort of gift or a refund for all the trouble but they said that, as they’re a support center, they can’t and if I want I can send a letter to their lawyers. Another terrible story from Dell support service.
But ehy, every Dell pc has a service tag which identifies every pc (with that tag they even know the name of the owner) so they are supposed to know every part of the pc
The problem with Dell is they change part numbers so fast that a particular part number replacement not be available, you then run not well trained techs trying to figure out which newer part number actually works and is equivalent on your model.
Last year I purchased three XPS 17 laptops within 3 months of each other for a client. Each time I had to choose slightly different options as they didn't offer the exact same configuration each time.