There has been some buzz about the plethora of XML standards and to what extent this might be a Bad Thing. Usually this is seen in terms of standards "fragmentation", which implies that an original standard has been broken up into more specialised forms.

Does anyone know of any resources that map out the evolution of XML standards, and how they relate to each other (either historically or in terms of the domains they address)? I wasn't paying attention to them, except for the ones I needed for EJB's. Now I find that there are so many and my head is starting to hurt.

I tend to go to http://xml.coverpages.org for general XML information, but that site probably has WAY to much for what you want. They have a brief summary of the core standards at http://xml.coverpages.org/coreStandards.html but that probably does not have enough information.

It would help if you got more specialized. For example: XML specification related to Web Services. XML itself has become so ubiquitous that looking for an XML overview is almost like saying "I want to know all technologies that use UTF-8 or TCP/IP in some way".