Address dbaron's comment wrt 2.1-synchronization error in default object size; mark the list informative <http://lists.w3.org/Archives/Public/www-style/2012Mar/0336.html>

Author: fantasai

css3-images/Overview.html

@@ -1853,7 +1853,7 @@ <h3 id=sizing-terms><span class=secno>5.1. </span> Object-Sizing
      dimensions. It varies based on the context in which that the image is
      being laid out.</p>
 
-    <p>The following list defines the <a
+    <p>The following informative list defines the <a
      href="#default-object-size"><i>default object size</i></a> of properties
      and contexts that appear in CSS 2.1, plus &lsquo;<code
      class=property>border-image</code>&rsquo; from CSS 3 Backgrounds &amp;
@@ -1895,8 +1895,9 @@ <h3 id=sizing-terms><span class=secno>5.1. </span> Object-Sizing
      <dt>replaced elements
 
      <dd>The <a href="#default-object-size"><i>default object size</i></a> is
-      a rectangle 300px wide and 150px tall. <a href="#CSS21"
-      rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>
+      a the largest rectangle that has a 2:1 width:height ratio, is no larger
+      than 300px width and 150px height, and has a width that fits in the
+      device. <a href="#CSS21" rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>
     </dl>
   </dl>
   <!-- ====================================================================== -->

css3-images/Overview.src.html

@@ -1095,9 +1095,9 @@ <h3 id="sizing-terms">
 			<i>intrinsic dimensions</i> and <i>specified size</i> are missing dimensions.  
 			It varies based on the context in which that the image is being laid out.</p>
 
-			<p>The following list defines the <i>default object size</i> of properties
-			and contexts that appear in CSS 2.1, plus 'border-image' from CSS 3
-			Backgrounds &amp; Borders.
+			<p>The following informative list defines the <i>default object size</i> of
+			properties and contexts that appear in CSS 2.1, plus 'border-image' from
+			CSS 3 Backgrounds &amp; Borders.
 			Newer modules that accept an ''&lt;image>'' component value in a new
 			context must define the <i>default object size</i> in that context.</p>
 
@@ -1115,7 +1115,7 @@ <h3 id="sizing-terms">
 				<dd>The <i>default object size</i> is a UA-defined size that should be based on the size of a typical cursor on the UA's operating system. [[!CSS21]]</dd>
 
 				<dt>replaced elements</dt>
-				<dd>The <i>default object size</i> is a rectangle 300px wide and 150px tall. [[!CSS21]]</dd>
+				<dd>The <i>default object size</i> is a the largest rectangle that has a 2:1 width:height ratio, is no larger than 300px width and 150px height, and has a width that fits in the device. [[!CSS21]]</dd>
 			</dl>
 		</dd>
 	</dl>