No mention on any compression that is being done on the scripts that are being delivered, either through gzipping components or reducing the file size through use of a compression script like YUI, Packer, etc.? I know that compression scripts probably through your who study out of whack (i.e. ignoring the fact that it is not publicly available, I doubt that you could determine that the Website builder application my company offers uses Prototype/Scriptaculous in our admin area because we run a script to compress them into one file to save on HTTP requests, then run them through YUI to save bandwidth).

I'm sure compression is another article, but it is probably worth mentioning when you're talking about script size.