Pastoid

I've been trying to build a best-case HTML5 template for Habari-powered blogs, something that is semantic, flexible in its ability to have CSS applied, and uses schema.org metadata liberally for machine-readability.  One of the more helpful resources I've found is Edward O'Connor's HTML5 blog template case study (edward.oconnor.cx/2009/09/using-the-html5-sectioning-elements), which gives a good outline of how to create a semantic blog template.  Nevertheless, this seems slightly incomplete.
 
When outputting a blog entry, authors usually want to include metadata about the post, including publication date, author's name, and categories or tags.  I've been toying around with some HTML5 elements looking for the best candidate, and am so far unhappily using the details element.  Have a look at the sample output here: 07test.habari.me
 
Essentially, the summary element displays what most people want to see, where the details within it are a useful expansion of that information.  I suppose I'm making an assumptive leap in thinking that the information within the details element should be structured or somehow usefully machine-readable, but as far as I can tell, there is no useful way to output for display via HTML that is also machine-readable.
 
The set of elements that seems most logical to use would be either dl/dt/dd or tables, but these both suffer from not having any way to have directed key-value pairs.  For example, you can't easily say that the value of this dt refers to the value of that dd, or that a specific th is the label for a specific td.
 
So my question is actually two:  First, is there a way to visibly display structured key-value data in HTML that can also be read easily by a machine?  Second, if the details element is not the best for the purpose of displaying the post metadata, what semantic element is?