This article on boxesandarrows is a mostly flamebait and I should avoid commenting on it. But I can't resist. First he constraints his argument to a mythical universe where SVG, MathML, SMIL, and XForms don't exist. Then says since he can't do everything he wants to in that tiny realm the only alternative is to go with proprietary technologies. His excuses include:

Bandwidth
Sorry, there's no way in hell your JavaScript and CSS, which should be in seperate files and cached on the client, even come close to the size of image files. And even if they are turn on mod_gzip and they'll skrink to a third of their current size.
Accessibility
You can't be seriously putting Flash, Curl or Java up against HTML for accessibility.
Where is the application?
This sounds like a lame excuse for poor design. Especially, given this quote: Users also insist on being able to use a ~Back~ button, which can cause page and link management issues, especially if you are trying to use frames to solve other problems. Frames? Fretting about users using the back button? This is ludicrous.
Accessing the desktop
He does have a very minor point here on uploading files being a pain, but everything else is a security nightmare. Of couse if you followed good RESTian principles in the design of your system you could have a standalone thin client that does the uploading for the users that need it while still presenting the web interface to the rest of the users, with no change to the backend.

Ok, I feel much better now. We return you to your regularly scheduled programming.