This is very exciting news, especially knowing that this significantly better-looking theme is coming to desktop JQuery UI. One of my biggest issues with JQuery UI has always been how goofy it looks in comparison to Aristo and Ace (http://www.antipode.ca/2009/themes-sproutcore-vs-cappuccino/)
Wow - in Chrome on Windows 7, that Sproutcore sample page uses 40% of one core of an i7 just sitting there doing nothing. Hopefully that doesn't carry over to a mobile Webkit browser as well...
the mobile ui elements the jquery team is building is the best i've seen so far. they've done a spectacular job there. i hope that as with jquery themeroller, the ui elements for mobile will be customizable.
Yep - they're going to be 100% Themeroller-able. It's going to be a bunch of work on our end but the ability to have a unified, good-looking, UI that works across all platforms is just too enticing to ignore.
Did you consider pre-rendering stuff client-side using SVG? I assume adjusting a few parameters in a JSON file is easier than going to a site, pushing buttons and downloading and replacing files.
We're looking into every possible idea we can to shave file size and images down for mobile. Look for very aggressive use of CSS3 that falls back gracefully. We're hoping to eliminate all images (!) or radically reduce their use compared to current ThemeRoller. Using SVG is an option on the table for some elements but I think we'll end up using a TR style tool for this to generate static CSS for performance and compatibility.