[rockymeza]

I work on widgy, so I admit that I'm very biased, but I'd like to expand on this a little bit.

I think there are some use cases where the tree structure really shines, where I haven't really seen anything that could really match the power that we give the user. For example, the Form Widget -- users can create their own forms just by dragging and dropping the form input widgets. Now this would be possible without the tree structure, but since we have it in widgy, users are able to intersperse non-form related widgets like text or images and also they can add structure widgets like the Tabs or Accordion widget.

> I also take your point about the tree of widgets thing, but there is always a trade off between conceptual-ease-of-use and power.

We do find that our clients are willing to take a little time to learn the interface in exchange for the ability to have more power.