So one of the major issues web apps face these days is the horrendous landscape of browsers that could be used. It’s not only the inconsistencies between, but also the bugs – you have to code in certain ways because of ie8’s bug when dealing with XYZ. So the user gets to choose a browser, but the dev has a nightmare.
So, why can’t we embed a browser in a browser? You might need to get all the major browsers to sign on, but essentially if you use a webapp, it “embeds” the browser of the dev’s choice, all actions take place on that, and the display is drawn to a canvas in the main browser. The idea is then that the dev can choose a platform to develop against. ‘course the download for each app you use would go up, but maybe it could all be cached.