I've been researching a jQuery drag and drop tree plugin for a project that I'm working on and so far I've found the following:
So far this is my favorite. It does almost everything that I want including in place editing of the tree items. One drawback is that it itself requires a ton of plugins to work and is complex to setup and this makes it brittle in my opinion. The creator, however, is frantically working on a new release which I think will simplify things and dramatically improve this already excellent plugin. I've decided that this is the one that I'll probably use but will wait until the next major release comes out.
Fantastic set of demo pages - this is what "sells" plugins - if you don't have a create demo page then you will dramatically reduce your chances of getting users to use your plugin.
Good but does not support in place editing. Big plus that it has a demo page but the demo is fairly simple and I suspect that it has more features that have not been demo'd.
The demo looks reasonable but no work has been done on this (so it seems) since 2007 and there's not much other documentation about this plugin.