I, too, would like to see other browser vendors follow and I don't see the same obstacles as with video codecs so there's hope yet. Microsoft's plans for IE auto-updating should also help (if they decide to support WebP) but admittedly it'd still be a long wait for web developers.
We (Opera) started supporting WebP not long after its release and it's proved to be an effective improvement on JPEG. IIRC, there's a roughly 30%-40% reduction in image filesizes when used as part of our server-side compression feature (Turbo) which converts all JPEGs into WebP (among other stuff).
Of course, support in all modern browsers and being able to use WebP exclusively in public sites are not closely connected, unfortunately, but for sites with high image usage, detection for support and server-side image replacement could be worthwhile.
We (Opera) started supporting WebP not long after its release and it's proved to be an effective improvement on JPEG. IIRC, there's a roughly 30%-40% reduction in image filesizes when used as part of our server-side compression feature (Turbo) which converts all JPEGs into WebP (among other stuff).
Of course, support in all modern browsers and being able to use WebP exclusively in public sites are not closely connected, unfortunately, but for sites with high image usage, detection for support and server-side image replacement could be worthwhile.