Rated 5 out of 5 stars
I think Mozilla has done a good job on the nightly versions with the 'allow now' or 'allow and remember' options for the plugins, which will render this add-on unnecessary.
Edit: yo, thanks for the reply, I saw that thing on the permissions tab too. :)
You my be right, the new permission system looks promising.
But I am thinking about integrating this into my addon to allow the change of these options with a single click to a button, which would also allow these setting per domain.
Because when you clicked "allow and remember", to deactivate this behaviour you would have to open the site information window, find the right tab, etc... ;-)