[ProgramMax]

Strangely, I was familiar with AIFF and RIFF files but never made the connection that they're both IFF. I hadn't known about IFF before your post. Thank you :)

W3C requires that we do not break old, conformant specs. Meaning if the next PNG spec would invalidate prior specs, they won't approve it. By extension, an old, conformant program will not suddenly become non-conformant.

I could see a group of people formalizing IFFv2, and adapting PNG to it. But that would effectively be PNGIFF, not PNG. It would be a new spec. Because we cannot break the old one.

That might be fine. But it comes with a new set of problems, like adoption.

Soooo I like the idea but it would probably be a separate thing. FWIW, it would actually be nice to make a formal IFF spec. If there was no governing body that owns it, we can find an org and gather interest.

I doubt W3C would be the right org for it. ISO subgroup??

[saintfire]

They pretty much say the same thing halfway through. Don't change PNG but adapt IFF to work with PNG's flavour of IFF.

[ProgramMax]

Right. Sorry, that was supposed to be a "yes, and..." to provide some additional context.