These are the ones that I currently think are important enough to include:
Identifier
<meta name="DCTERMS.identifier" scheme="SCHEME NAME" content="SCHEME CODE" />
Title
<meta name="DCTERMS.title" content="TITLE" />
Author
<meta name="DCTERMS.creator.aut" content="NAME" />
Series Name
<meta name="DCTERMS.isPartOf" content="SERIES NAME" />
Series Number
<meta name="DCTERMS.hasPart" content="SERIES NUMBER" />
Type
<meta name="DCTERMS.type" content="GENRE or CLASSIFICATION" />
Subject
<meta name = "DCTERMS.subject" content="KEYWORD(S)" />
Description
<meta name="DCTERMS.description" content="DESCRIPTION OF CONTENT" />
Publisher
<meta name="DCTERMS.publisher" content="PUBLISHER DATA" />
Publication Date
<meta name="DCTERMS.issued" content="YYYY(-MM(-DD))" />
Creation Date
<meta name="DCTERMS.created" content="YYYY(-MM(-DD))" />
Modification Date
<meta name="DCTERMS.modified" content="YYYY(-MM(-DD))" />
Copyright Date
<meta name="DCTERMS.dateCopyrighted" contents="YYYY(-MM(-DD))" />
Copyright Holder
<meta name="DCTERMS.rightsHolder" contents="NAME/ORG." />
Copyright Status
<meta name="DCTERMS.license" contents="LICENSE/STATUS" />
Language
<meta name="DCTERMS.language" content="TWO-LETTER LANGUAGE CODE" />
Source
<meta name="DCTERMS.source" content="SOURCE DERIVED FROM" />
==================
Any additional creator or contributor may be added using the over 200 MARC Relator Codes:
Illustrator
<meta name="DCTERMS.creator.ill" content="NAME" />
Proofreader
<meta name="DCTERMS.contributor.pfr" content="NAME" />
Editor
<meta name="DCTERMS.contributor.edt" content="NAME" />
Cover Designer
<meta name="DCTERMS.contributor.cov" content="NAME" />
==================
Extensions that don't meet the DC spec, but do meet the ePub spec:
File-As
<meta name="DC.creator.aut" scheme="FileAs:Lastname, First Middle" content="Dr. First Middle Lastname, Esq." />
-- Part of the ePub spec, but generally useful to define document sorting. The scheme attribute will be ignored by any parser as an unknown scheme.
==================
Others that maybe SHOULD be included (please make an argument against):
==
Abstract
<meta name="DCTERMS.abstract" content="SUMMARY OF CONTENT" />
-- I could be talked into this one. More useful for non-fiction.
==
Alternative Title
<meta name="DCTERMS.alternative" content="TITLE" />
-- Alternate Title, like a foreign name, or earlier (maybe offensive) name. This is more common than I originally thought.
==
Audience
<meta name="DCTERMS.audience" content="INTENDED AUDIENCE" />
-- Like age-ranges, or... something else? "Young Adult" is a really popular category at the moment.
==
==================
Others that should maybe NOT be included (please make an argument in favor):
Format
<meta name="DCTERMS.format" content="MEDIA/FILE TYPE" />
--I'm of a mind that it being an eBook, you're already pretty sure of the media and/or filetype.
==
Relation
<meta name="DCTERMS.relation" content="RELATED RESOURCE" />
-- The two refinements of this that allow us to keep Series Name and Series Number seem adequate.
==
Coverage
<meta name="DCTERMS.coverage" content="TIME, SPACE, or OTHER SPAN" />
-- Meh. Subject seems enough.
==
Provenance
<meta name="DCTERMS.provenance" content="OWNERSHIP HISTORY" />
-- I think this is about the actual, physical resource. I'm not sure it's relevant to an ebook.
==
Access Rights
<meta name="DCTERMS.accessRights" content="PERMISSION(S) TO ACCESS" />
-- Things like age restrictions, etc. Talk me into it. It'll be hard, I'm against most restrictions, even normal ones.
==
Date of Acceptance
<meta name="DCTERMS.dateAccepted" content="YYYY(-MM(-DD))" />
-- Some certifying authority acknowledges receipt/acceptance of a document. Meh.
==
Date of Submission
<meta name="DCTERMS.dateSubmitted" content="YYYY(-MM(-DD))" />
-- Some certifying authority is given a document. Double-meh.
==
Geographical/Spatial Coverage
<meta name="DCTERMS.spatial" content="SPATIAL RANGE" />
-- Seems unnecessarily redundant of the Coverage tag.
==
Date/Temporal Coverage
<meta name="DCTERMS.temporal" content="TEMPORAL RANGE" />
-- Also seems unnecessarily redundant of the Coverage tag.
==
Has Version
<meta name="DCTERMS.hasVersion" content="TITLE/NAME" />
-- Indicates another resource that is adapted from this one.
==
Is Version Of
<meta name="DCTERMS.isVersionOf" content="TITLE/NAME" />
-- Indicates a resource that this resource was adapted from.
==================
Undefinable by DCTERMS, but possibly desired metadata:
File Name
-- The original name of the eBook file.
File Version
-- Using a defined versioning scheme. It's also a bit like a "#th Printing" statement.
File Comment
-- Information about how/why the ebook file was created.
Sub-title
-- Lots of books have these.
Publication City
-- Commonly used. Might be growing less relevant in the digital age.
==================
I'm always open to input, corrections and suggestions!
There are other ways to code this, but I'm looking for a relatively simple, consistent method that covers most everything. The DCTERMS namespace seems to be that method, as the DC namespace is more limited and requires a somewhat vague extension ("refinements").
Also, all the DCTERMS can be defined this way in XHTML, but the questions here are: What is generally useful for eBooks? What are absolutely necessary, what are not?
I'll update this post as it gets better defined.
m a r
ps: huge props to KevinH!