The plug-in, which is available for download at: https://sourceforge.net/projects/crossref-cite/, allows the blogger to use a widget-based interface to search CrossRef metadata using citations or partial citations. The results of the search, with multiple hits, are displayed and the author can then either click on a hit to follow the DOI to the publisher’s site, or click on an icon next to the hit to insert the citation into their blog entry (as either a full citation or as a short “op. cit.”).
So far the tool is only available for WordPress blogs. The idea is that bloggers can use DOIs to uniquely identify papers that they are discussing, while at the same time providing readers with an easy way to go to the site hosting the article, and aggregators such as postgenomic.com can cluster posts about the same paper.
Whilst Googling for reaction, I came across various posts extolling the virtues of OpenURL versus DOIs, or proposing alternative identifiers (DOI or DOH? Proposal for a RESTful unique identifier for papers, and PaperID - An Open Source Identifier for Research Papers). Personally I think much of this discussion focusses on identifiers, when it's the services built on those identifiers that really matter.