W3C will be the way to go long-term, but first we want to have as much real-world experience with this thing as possible. And that is what the current JavaScript implementation enables for us and others. Specs should never be made in ivory towers!
As for performance, that sounds very dubious given that even my Nexus 7 does this thing at 60fps
Running into the same jank issue as well. Chrome 33, Macbook Pro i7 w/ 16gb RAM. While I'm not at 30fps (averaging in the 40s), there are definitely some frames being dropped.
could this be happening because of bad video drivers? gss uses css transforms to speed up rendering and a bad video driver can cause a browser to automatically switch down to software rendering of 3D transforms.
If GSS requires 3D acceleration to get good performance, I'd say that it needs some serious optimization somewhere.
Adding another slow layer is not really helping anything: by the time you have browser-C++-overhead + DOM overhead + JS interpretation/V8/SpiderMonkey overhead, adding another layer on top of this all is really not wanting to make me develop on this platform.
As for performance, that sounds very dubious given that even my Nexus 7 does this thing at 60fps