Tim’s Wannabe Five

I don’t know how I missed this before, but Tim Bray blogged about not inventing XML languages over a month ago. This comment is right on the money: “The value of a markup language is proportional approximately to the square of the number of different software implementations that can process it.” Conceptually, I agree with him – my primary argument against XSPF is that it has the same basic semantics as RSS, but RSS is much more widely used. But his list of the “big five” markup lanugages seems more like the “wannabe five”. How many different siftware implementations process any of the things on his list?

I’m not arguing the technical quality of these lanugages – frankly I’m not that familiar with any of them but Atom. But if you’re arguing the network effect, none of these formats Tim lists qualify. I’m sure he wants them to be popular, but wishing doesn’t make it so.