Yes, drag'n'drop is a new and cool feature that other treeview can not campare of.

You can get more information about this feature, just follow this link:
http://www.justrun.net/products/skytree/DragDrop.html
Or you can take a direct view of the online demo:
http://www.justrun.net/demo/skytree/Demo/Demo_JSON.html
And more resouce can be found in Skytree online help: