See also woopra integration - !http://www.woopra.com/wp-content/uploads/2008/08/woopra-wordpress-plugin.jpg - !http://weblogtoolscollection.com/archives/2008/04/27/woopra-and-wordpress-unofficial-coolness-guide/
Robert, I think we just want to help plugin authors building such features if they want to. We don't want to take over wordpress integration plugin for now, as already there are a few plugins that you mentioned that are doing a nice job. I mark this one as fixed for now.
See also the blog post on piwik.org http://piwik.org/blog/2008/06/new-plugin-wordpress-piwik-integration/