I am very surprised to see that Chrome 24 doesn't list WebP support in its HTTP Accept request headers*.
I've had a good look at the WebP home page but it does not mention how best to detect for WebP browser support.
Ideally, I would have thought most web developers would want to check for support in a HTTP Accept request header then use server side logic to determine whether to serve WebP or drop back to JPEG/PNG.
I realise one could detect for specific versions of Opera and Chrome via the HTTP User-Agent but this will require ongoing maintenance (when Firefox and Safari add support, for example).
Would be great to see Google's official recommendation for detecting WebP browser support posted to the WebP homepage. Web developers would have more confidence to support the format and therefore drive its mainstream adoption forward.