This past week the W3C announced the publication of a working draft of RDFa in XHTML: Syntax and Processing in their Semantic Web Activity News Weblog which includes an RSS feed.

I include a Semantic Web/RDF Overview/Reference compilation via the link in my signature block.

James

The situation with XHTML+RDFa will be similar to the one that exists with present XHTML 1.0 as far as included XML content is concerned (served as application/xhtml+xml). However, associated rdf/xml content will be usable with XHTML+RDFa The XHTML+RDFa Doctype is now cataloged and I have composed a test page using content negotiation: content (MIME) type text/html for IE Browsers and content (MIME) type application/xhtml+xml for Firefox, Opera, Safari, et al.

Check RDF Validation results for the RDF/XML feed at the bottom of the page and the RSS live feed.

James

Added via Edit -- eventually I removed this test document inasmuch as the W3C reference document is still only a draft.

This post has been edited by jamesicus: Mar 22 2008, 12:28 AM

The Semantic Web is now on the fast-track at the W3C and we are being bombarded with a plethora of documents, position papers, recommendations, etc.

XHTML+RDFa is obviously still experimental (RDFa in XHTML: Syntax and Processing is only a draft). I personally use RDF/XML online for producing my RSS feed and manipulating Dublin Core Metadata -- my major use of RDF is for categorizing, sorting, organizing, and micro-searching Roman coin collections, extracting metadata/data from my web pages.

The vision of Tim Berners-Lee (inventor/creator of the WWW and Director of the W3C) is that the future direction of the Web lies with the Semantic Web as presently defined.

I have my own opinions -- I may be completely wrong in my assessments and predictions, but here goes:

At present I think the whole concept of the Semantic Web/RDF (and XHTML+RDFa?) is far too complex and hard to understand -- my experience has been that most people seem to roll their eyes in bewilderment when they even glance through a Semantic Web document -- sometimes their eyes glaze over. I think that the concept is going to be a hard sell to the Web Authoring Community anyway -- I also think all the documents are going to have to be extensively simplified before they are usable in a practical way. On the other hand, I think the Semantic Web will eventually become a powerful -- probably irresistable -- force, but not soon.

Again, In my opinion, XHTML has been a mess from the start. As it stands in the draft of the Syntax and Processing document, RDFa in XHTML should be served as application/xhtml+xml (edit) ala XHTML 1.0 the W3C is serving their Semantic Web (XHTML+RDFa) documents as text/html -- but I am sure they are just experimenting. Of course the big question is: When will Microsoft support Content (MIME) Type application/xhtml+xml in their IE Browsers? Until it does (doesn't seem likely soon) XHTML+RDFa (like "real" XHTML 1.0) will not be universally usable. Again, XML/RDF will render in XHTML+RDFa if it is externally linked (as it will in XHTML 1.0 served as text/html for that matter).

James

This post has been edited by jamesicus: Mar 22 2008, 12:41 AM