The FFmpeg-forked Libav project now has support for decoding Google's WebP format.
WebP hasn't taken off quite like WebM/VP8, but but the image format with lossy and lossless compression support is still around and seeing some adoption.
WebP is supported by modern web-browsers and some popular web-sites and desktop programs. The latest to support this image format that can compress much better than PNG is libav. With this Git commit
that was merged today and spotted by Anzwix
is a PNG decoder for the open-source multimedia library.