Re: Soon to come non-standard .xml...?
What this sounds like to me is a binary storage mechanism with ease of read-only access into it.
Think MongoDB's BSON or maybe a pre-computed protocol buffers type data structure for the metadata.
XML was the problem - large bulky datasets that were being validated and all that crap. Here we are serving known-good read-only data. Simplify and compact to death and provide an easy shim layer to read the data directly. Maybe just store it ready to put onto the network without transform - literally just arraycopy the required records out of the data structure into the datagram packet :p