I think the concept of having something that looks like a desktop and having the ability to place links on the desktop is appealing. It’s just another way of presenting objects in the framework layout as opposed to the current layout options
I can definitely think of some applications that could benefit this type of layout.
This example is also featured here as a web desktop under the demos at EXt-js http://www.extjs.com/deploy/dev/examples/desktop/desktop.html
However for the time being, I would rather see things like upgrading to Ext 3.0 and some additional features on the grid such as :
Group Summary http://www.extjs.com/deploy/dev/examples/grid/totals.html
and also
FeedViewer
http://www.extjs.com/deploy/dev/examples/feed-viewer/view.html