W3C Efficient XML Interchange WG is a GO!
The W3C Advisory Committee has a approved the creation of the Efficient XML Interchange (EXI) WG. This WG will be chartered for 2 years to look at the standardization of an alternate (read binary) format for XML. Sun has been involved in this activity since the beginning, and even hosted the first W3C workshop to address the need for alternate encodings back in Sept. 2003.
If your organization is a W3C member, you should have access to the official announcement. Interestingly, despite all the negative press we've seen in the last few years, only one member strongly opposed to the creation of the WG. The charter for the WG is available here.
The creation of a new XML format that could be transparently integrated into most XML applications (an example of which is, obviously, Fast Infoset) will help XML's adoption in several sectors in which it has been thumbed down thus far. Many of those use cases can be found in the XBC Use Cases document.
XML has transcended from a cool data representation format into an enormously powerful set of technologies which we now refer to as the "XML stack". A more efficient XML format will enable the use of this XML stack in places for which it was not possible to do so. Thus, this initiative is not about breaking, jeopardizing or fragmenting XML; it is about unifying, embracing and expanding XML's scope so that a single, truly horizontal format can be used to exchange data from the data center to a Java card.