"XML was frozen and published in February 1998. As it came toward the end and it became obvious -- well, not obvious, but likely anyhow -- that this was going to get a lot of momentum, we were besieged by requests for extra features of one kind or another. We basically lied and told the world, we would do all that stuff in version 2. You have to shoot the engineers and ship at some point, right? I think there will never be an XML version 2. There is an XML version 1.1, but it's controversial and not widely supported." Tim Bray (via Dave Winer)