APNG has very slowly (but steadily) gaining popularity. One of the recent things I was told about is the current list of most popular ideas Ubuntu Brainstorm: APNG Support.
I’ll put a screenshot here for posterity:
That’s pretty cool. The thing that makes me feel best is the overwhelming positive votes. Looking at the rest of the ideas on the website – most of them don’t have even 50% of the votes positive.
Neat! Maybe there will be APNG in Ubuntu. Not that it will make any difference to libpng proper, those guys are too stuck up. But maybe given enough forks they will reconsider.