It's fast because I didn't both with a mobile web framework. I've found those (especially jQuery mobile with its DOM caching) to perform horribly. This should scroll as quickly and smoothly as your phone can.
...and you're totally right about jQuery Mobile causing suckage. I used it for a couple features and I'm now ripping it out in favor of a little handrolled solution I built. I even replaced the jQuery core library with XUI because it's even smaller has most of the goodies I use 99% of the time.
For everything XUI doesn't have, I really like XUI.extends in its simplicity better than the jQuery plugin architecture. Super easy to add whatever else you need.
Performance is night and day better now.