I find that they are quite relevant. In fact, I begin by prototyping all new app-ish projects as mobile web (twitter bootstrap). Then, if we need better acces

I find that they are quite relevant. In fact, I begin by prototyping all new app-ish projects as mobile web (twitter bootstrap). Then, if we need better access to phone features (push messaging), I will simply wrap it in cordova. Admittedly, I do have to fight with some plugins, but I try to not stray too far from well supported ones. Also, you should know that you can get 60 frame/second on canvas. There are may casino slot style games that do just this. I believe flipboard does as well?