The new PRISM spec (v. 2.0) was published this week, see the press release. (Downloads are available here.)
This is a significant development as there is support for XMP profiles, to complement the existing XML and RDF/XML profiles. And, as PRISM is one of the major vocabularies being used by publishers, I would urge you all to go take a look at it and to consider upgrading your applications to using it.
One caveat. There’s a new element <tt>prism:doi</tt> (PRISM Namespace, 4.2.13) which sits alongside another new element <tt>prism:url</tt> (PRISM Namespace, 4.2.55). Unfortunately the <tt>prism:doi</tt> element is shown to take DOI proxy URL as its value - and not the DOI string itself, e.g.