High Scalability Building bigger, faster, more reliable websites.

I've been using GWT for an application and I get the same feeling using it that I first got using html. I've always sucked at building UIs. Starting with programming HP terminals, moving on to the Apple Lisa, then X Windows, and Microsoft Windows, I just never had IT, whatever IT is. On the Beauty and the Geek scale my interfaces are definitely horned-rimmed and pocket protector friendly. Html helped free me from all that to just build stuff that worked, but didn't have to look all that great. Expectations were pretty low and I eagerly fulfilled them. With Ajax expectations have risen again and I find myself once more easily identifiable as a styless geek. Using GWT I have some hopes I can suck a little less.

In working with GWT I was so focussed on its tasty easily digestible Ajaxy goodness, I didn't stop to think about the topic of this site: scalability. When I finally brought my distracted mind around to consider the scalability of the single page webs site I was building, I became a bit concerned. Many of the strategies that are typically used to achieve scalability don't seem to apply in single page land. Here are the issues I see. Maybe you can tell me where I am off in my analysis?