Impact is nice, but HTML5 still has 3 major issues in my opinion. 1) Sound doesn't work on every platform/browser but this is not impact's fault, it's html5.

Impact is nice, but HTML5 still has 3 major issues in my opinion. 1) Sound doesn't work on every platform/browser but this is not impact's fault, it's html5. 2) Performance on android isn't good. It works ok in Opera, but not well the default browser. 3) In-browser multitouch on android is not available yet.