Someday I'd like to make a drag and drop treeview for moving pages around. I could easily put the current listview in an updatepanel to ajaxify it but I really don't think that would speed it up, it would only make it a little smoother looking. When a page is moved, all the pages with the same parent have to be re-ordered, so the list has to be re-populated after each move and the list is the only thing on the page so its not going to save much time. Also, when a page is moved the menu itself has to change so doing it in an ajax panel would leave the menu unchanged and it could be more confusing. I've got too many other fish to fry to look into this right now.
Best,
Joe