The biggest problem is that the camera companies are racing forward passing any and all standards as they go.
The whole "Private Maker Note" issue comes from the lack of enough defined public tags for EXIF. EXIF is a standard originally proposed by Kodak, adopted by the www.exif.org
and then coopted by the JEITA (Japan Electronics and Information Technology Association). The last publicly available standard is EXIF 2.2 (April 2002) but I'm pretty sure most cameras are at 2.3 or 2.4. It seems that the JEITA has been pretty lax publishing the changes. . .but the problem is that new public fileds have not been defined so new cameras that contain new types of metadata are forced into using private maker notes-which is where the whole problem gets super sticky.
Then you move on to TIFF-EP which is the basis for most EVERY raw file format out there. . .the last published standard for TIFF-EP I can find is from 1998 or 1999. Well, a LOT of stuff has happened since then and the standard has simply not moved forward. . .
Why? There is no incentive for the camera makers to hold themselves to any standards. . .they don't WANT to be held to any standards.
There is another sinister reason perhaps. . .and you need to put on your conspiracy hat to delve into this speculation-and all it is is speculation mind you. I'm not making any accuations here, just speculations. . .
What if they have something to hide? What if by adopting a tough stance on proprietary and undomented raw file formats they (the camera makers) are hiding the fact that a whole bunch of patents are being steped on. If they can hide behind the undocumented, proprietary raw file format, they could be hiding the fact that they are violating a lot of exisiting patents. . .perhaps by Kodak or pehaps by a variety of other US and European companies. Nikon has been incredably "busy" the last couple of years putting a lot of patents in place for a lot of various aspects of digital photography.
The reason I wonder about this, and again, I stress this is speculation, a couple of years ago Microsoft started to asert the patents held for DOS and the whole compact flash card file system. You haven't heard much about that. . .recently there was some news about Forgent suing Microsoft over data compression techniques Forgent claims is used in the JPEG digital image standard and in wide use throughout the industry.
Forgent had sued 31 companies in April 2004 and several other companies after that. The company has reached licensing agreements with more than 35 companies and received more than $100 million in licensing revenue to this point.
That patent is due to expire 2006 or 2007. (can't remember which)
One wonders if the camera makers are just trying to buy time. . .to save money and avoid litigation. . .