Highly impressive & useful widgets & utilities are in planing (& some are in development for a very long time) as listed in the WIKI:
http://jqueryui.pbworks.com/

It is listed there for a very long time & the UI development seems to be very slooooow! Why is this?

(Why jQuery not come as a commercial product & employ more workforce? Undoubtedly there is a massive market for jQuery!)