I seriously believe that Shumway is a very cool research project to demonstrate what is possible in modern browsers. But I just want to highlight a few things:
1. You mention that this can help in terms of CPU utilization, battery life, etc.
Would be great, still today, the very simple (non AS3/vector based) Racing game (http://mozilla.github.com/shumway/examples/racing/) you are running through Shumway requires around 70% of CPU usage on my MacBook Pro against 11% with Flash Player. A game which would consume even less in Flash Player if it used AS3 and simple bitmap blitting techniques. Yes, JS performance will improve, and efforts like River Trail are promising, but we are still far from that, I am a little worried we are setting the wrong expectations here.
2. The restaurant websites.
Yes, there are a lot of these restaurant websites using Flash. And to be fair, they should never have used Flash for that. But you are right most of them are porting these to HTML and it works nicely. But fortunately Flash on the web is not used for restaurant websites only, especially games. Today Flash Player is used to power 9 of the top 10 Facebook games with content like FarmVille 2, CityVille, Kings Road, Ruby Blast, Angry Birds targeting around 30 million daily users are powered with Flash Player using Stage3D and without Flash, we would all be playing Racing games like the one mentioned earlier. Or maybe faster games, but with NaCl in Chrome only? ;)
3. You don't see Flash rallying on desktop, or even via Air on Android.
Thanks to Stage3D, AIR is actually becoming more and more serious for game developers. Most developers wanting to develop games on desktop, iOS and Android are facing big issues when it comes to fragmentation and AIR solves that. All the mobiles games here http://gaming.adobe.com/showcase/ are using AIR.
1. CPU utilization will get better. We have a lot of low-hanging fruit yet to harvest (eg. the playerglobal built-ins aren't JIT'ed yet as we dogfood the interpreter.)
2. Facebook games running Flash are still a huge % of crashers for all Flash-enabled browsers. We'd like to help that. As browsers like Chrome sandbox away Flash's ability to be faster than the browser (i.e no more direct GPU access on Pepper) then Shumway becomes much more attractive, especially on mobile platforms for which there is no Flash Player.
3. SWF as a packaging format for app store deployment is a pale shadow of what we set out to do when we started working on it years ago. SWF could still outlive us all (like JPEG, HTML etc.) Shumway may well be the best bet to keep it alive.
2&3. I did write "(outside of Air and games, let's say)". Did you miss that?
See also Emscripten, which produces GC-free well-typed JS. We're also working in Mozilla Research to show Emscripten + JS can competes on performance, and excel on reach, with alternative single-browser and proprietary approaches.