I've been having some fun with easel.js, an abstraction layer that makes programming interactive HTML5 code a little less painful. It's mostly about the canvas tag, but there are some other general purpose interactive nuggets too.
The library includes 20+ samples to help you learn the code, including a fancy moving bar graph and animated rats!
I modified the animated rat sample to show the loveable animal walking at different rates. Even with the IE9 RC, you need to keep a sharp eye on performance.
In my modified sample, I extracted a sprite and updated an img tag on every "tick" exposed by easel.js library. The screenshot below shows my processor when the tick frequency was at 1ms, 10ms and 50ms respectively.
This was just HTML, as the code doesn't use the canvas tag to implement the animation. I wonder how that would affect performance.
Here's my modified code from the easel.js samples; you'll need to reference the libraries if you want to run it yourself.
Modified extractFrame.html (2.18 KB) easel.js sample