I’ll believe it when I see it take hold. I personally don’t think this will happen in real life. Apps serve over HTTP sounds great when everybody have a gigabit connection with unlimited data. The reality is, we don’t, at least not for many years to come. So, I think this will go the way of many other Google projects. Or at least, it’ll be regulated to ChomeOS, where you’re most likely connected to WiFi or ethernet.
BTW, I thought it’s funny that they call it Dart. Dart on Android = DOA :-D.