AVIF is now the default format across all accounts if you use auto=format. AVIF format can also be forced as the output format with fm=avif. File sizes should drop by nearly 60% compared to JPEG & 35% compared to WebP, so that's awesome news for every project.
We've also made available the iptc=allow parameter to allow IPTC metadata (which contain attribution info) to pass through from the original JPG image to the transformed image.