[widgets] localStorage vs preferences

In the widgets API spec, what are the advantages of having a
widgets.preferences attribute when the window.localStorage is already
available on the window object?

I think we should:

 1. Drop widget.preferences, but require a UA to implement
[WebStorage] (which we already do!).
 2. Pre-populate the window.localStorage with the value of
<preference> elements in the config document (no events are fired
during pre-population!).
 3. "Protect" read-only preferences, meaning:
      A. At runtime, throw a NO_MODIFICATION_ALLOWED_ERR exception
upon any attempt to invoke the setItem() or removeItem() methods.
      B. upon the attempted invocation of the clear() method, a user
agent must not remove the key-values of the protected preference from
a storage area.

WDYT?

Kind regards,
Marcos
-- 
Marcos Caceres
http://datadriven.com.au