Plug-in strategy

Is there a strategy about developping plug-ins ?

I mostly think of high profile websites where anybody can post articles, such as facebook, linkedin or even techcrunch, engadget, gamespot, autoblog, etc.

DeadPool a couple of things I am thinking of include a javascript dropin that will handle some aspects that the browser wallet does not. This would imply the website has the ability to edit the base pages.
More broadly, a lot of these big sites have their own… but once we get a little momentum I would certainly entertain approaching to have an embeddable button like we see for facebook, pinterest, twitter etc…