Diving In section updates and a few details. microformats work in HTM…

…L3 onward, more accurate to say "HTML" in general, RDFa has been ported to HTML (no longer future tense), microdata is separate from HTML5, but designed with HTML5 specifically in mind.

extensibility.html

@@ -32,9 +32,9 @@ <h2 id=divingin>Diving In</h2>
 
 <p>Of course, <abbr>HTML</abbr> can&#8217;t please everyone. No standard can. Some ideas don&#8217;t make the cut. For example, there is no <code>&lt;person></code> element in <abbr>HTML5</abbr>. (There&#8217;s no <code>&lt;rant></code> element either, damn it!) There&#8217;s nothing stopping you from including a <code>&lt;person></code> element in a web page, but <a href=http://html5.validator.nu/>it won&#8217;t validate</a>, <a href=semantics.html#unknown-elements>it won&#8217;t work consistently across browsers</a>, and it might conflict with future <abbr>HTML</abbr> specs if we want to add it later.
 
-<p>Right, so if making up your own elements isn&#8217;t the answer, what&#8217;s a semantically inclined web author to do? There have been attempts to extend previous versions of <abbr>HTML</abbr>. The most popular method is <a href=http://microformats.org/>microformats</a>, which uses the <code>class</code> and <code>rel</code> attributes in <abbr>HTML</abbr> 4. Another option is <a href=http://www.w3.org/TR/rdfa-syntax/>RDFa</a>, which was originally designed to be used in <a href=past.html#postscript><abbr>XHTML</abbr></a> but is now <a href=http://www.w3.org/TR/rdfa-in-html/>being ported to <abbr>HTML</abbr></a> as well.
+<p>Right, so if making up your own elements isn&#8217;t the answer, what&#8217;s a semantically inclined web author to do? There have been attempts to extend previous versions of <abbr>HTML</abbr>. The most popular method is <a href=http://microformats.org/>microformats</a>, which uses the <code>class</code> and <code>rel</code> attributes in <abbr>HTML</abbr>. Another option is <a href=http://www.w3.org/TR/rdfa-syntax/>RDFa</a>, which was originally designed to be used in <a href=past.html#postscript><abbr>XHTML</abbr></a> but has <a href=http://www.w3.org/TR/rdfa-in-html/>been ported to <abbr>HTML</abbr></a> as well.
 
-<p>Microformats and <abbr>RDFa</abbr> each have their strengths and weaknesses. They take radically different approaches towards the same goal: extending web pages with additional semantics that are not part of the core <abbr>HTML</abbr> language. I don&#8217;t intend to turn this chapter into a format flamewar. (That would definitely require a <code>&lt;rant></code> element!) Instead, I want to focus on a third option which is part of, and tightly integrated into, <abbr>HTML5</abbr> itself: microdata.
+<p>Microformats and <abbr>RDFa</abbr> each have their strengths and weaknesses. They take radically different approaches towards the same goal: extending web pages with additional semantics that are not part of the core <abbr>HTML</abbr> language. I don&#8217;t intend to turn this chapter into a format flamewar. (That would definitely require a <code>&lt;rant></code> element!) Instead, I want to focus on a third option developed using lessons learned from the from microformats and RDFa, and designed to be integrated into <abbr>HTML5</abbr> itself: microdata.
 
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