Over the weekend I figured out a reliable way of converting WebP image data into CGImage data structures for easy compositing in Mac OS X programs. And until native WebP support starts to appear in browsers, which could take years, it's possible in the meantime to add WebP support to browsers through plugins.
I realize there's one downside to this, that webmasters will have to use the <object> tag instead of the classic & more appropriate <img> tag for displaying WebP images, but for the time being, the object tag works everywhere, and will be forward compatible as well.
So I created two Web browser plugins, one that uses the WebKit API and one that uses the Netscape API. They are collectively called "Weppy" and I'll release binaries tomorrow, but the source code & build instructions are now available here: <http://github.com/nickzman/weppy>
Nick Zitzmann
<http://seiryu.home.comcast.net/>