Don't forget iUI. :-) It's minimalist, but very lightweight and fast, and is great if you want a native-like iOS look-and-feel in a web app. http://www.iui-js.org/
Edit: as others have noted, there's some overlap. The project I currently have under development uses PhoneGap, jQuery Mobile, and iUI for different functions.
I'm creating a web app builder for non-technical people. It uses iUI for the generated apps (lightweight, gives a decent native-like look and feel) and jQM on the builder side (lets me leverage the tons of jQuery code out there).
Edit: as others have noted, there's some overlap. The project I currently have under development uses PhoneGap, jQuery Mobile, and iUI for different functions.