Flash and Java applets were (and are) kind of terrible, but the basic premise of compiled binary applications accessible as embeds in a browser is, I think, potentially more revolutionary than even that of the web as linked documents. It just may be that the first iteration of this was too primitive to realize its true potential, and the traditional javascript run "web app" is just an awkward interstitial phase we have to get past.

Although... I also think that at some point the line between the web, browser and operating system might have to blur or disappear entirely.