There's this thing about APNGs being used for animated sprites in Bulbapedia: It won't show in most browsers. As far as I know, IE, Chrome, and Webkit-based browsers won't work with them and only show the static frame.
This isn't good, as it limits the animations to certain browsers. Since they are sprites, with no more than 256 colours in the whole file almost all of the time, it makes no sense for them to be in the APNG format. Especially when GIFs can do the same thing at no loss of quality.
Also, the APNGs are actually bloated - recompressing them into GIFs yielded from a 5% to 60% size reduction. What's up with the APNG compressor, anyway?
There's a good reason why APNGs are not supported by most browsers. APNG is a rejected extension of PNG. It was rejected by the PNG group. Whereas, GIFs are supported by just about every browser.
I propose to reconsider our stance on animated sprites and use GIFs again for them. Any opinions?