So, I played a bit with CSS animations and I think this works pretty well: http://jsfiddle.net/dglazkov/wR8BP/1/ There are two stumbling blocks (filing them as bugs now) to this awesomeness: 1) We need to change positioning logic of the thumb -- it needs to set position of the thumb in the future, instead of the present. 2) We need to make input[type=slider] support CSS animations
For the first one, we can just use this bug.