Let's say you create a document with an image of a button for a website. The button label is a text layer linked to a variable. (Image -> Variable -> Define)
Now you save this document as "MyButton.psd"
Now you create another document – a design for a whole website. You place MyButton.psd as SmartObject into your document multiple times. But each time the buttons needs a different label text. So I would love to select the MyButton-SmartObject, see the variables defined inside the SmartObject and be able to edit them.
This would make in SmartObject more reusable.
P.S. Having LayerCompositions accessible in a similar way, would be great, too.