Virtually all major relational dbms now output XML, if crude, and there is not really much reason people shouldn't be doing so on some agreed upon alternative http port, say 8883.

I would advise against this... many institutional firewalls prohibit all packets except through port 80... this would effectively prevent all of our staff from playing with the outside world... bummer, but them's the rules...

It's not critical to wait for an agreed upon uniform schema to serve XML. it's even possible to infer a schema or DTD from data instances, and anyway a schema or DTD is not necessary to do much of what XML is good for.

but it is nice to be able to look at them to see what people think they are doing... :)

jim