AS3 is still ECMAScript, just a newer version of it. I do agree they're being left behind in optimization, after leading the pack for a while. Thankfully they'

AS3 is still ECMAScript, just a newer version of it. I do agree they're being left behind in optimization, after leading the pack for a while. Thankfully they're aware of it and they're working on it. Here's something that explains some of the optimizations they're doing to the player: http://arno.org/arnotify/wp-content/uploads/2011/04/Flash-Camp-Brasil.small_.pdf http://arno.org/arnotify/wp-content/uploads/2011/04/Flash-Ca... It's more about the multi-processor support (e.g network loading and some rendering on a separate thread) but it does talk a bit about the JITing and GC changes and whatnot.