The only reason I'd want these is for a web page to be used on an iPhone. They kill usability for keyboard-focused users.
It's a pretty damn good job.
<s>I bet it's not too dificult to add keyboard support to them</s>
Actually, it’d be nice to see a Webkit specific (or at least modern browser specific) JS library that dumps IE workarounds and fallback DOM selection routines; leaves us with syntactic sugar for QuerySelector and XMLHTTPRequest, and an animation library.