This notion always makes me laugh. Which is better, Google Maps or the old MapQuest pages that had arrows and reloaded the entire page when you wanted to move the map? I know which one I prefer.
I would agree that Actionscript 3 as an implementation of ECMAscript is more of a delight than JavaScript as a language which conforms to whatever version of ECMAscript. But compiling to VMs in the browser? Never again.