Updated GPL info

[SVN r22578]

more/license_info.html

@@ -135,10 +135,15 @@ license.</p>
 <a href="http://www.opensource.org/licenses/gpl-license.php">GNU General Public 
 License (GPL)</a>?</b></p>
 
-<p>The Boost license permits the creation of derivative works for commercial or 
-non-commercial use with no legal requirement to release your source code. Other 
-differences include Boost not requiring reproduction of copyright messages for 
-object code redistribution. The GPL is also much longer.</p>
+<p>The Boost license permits the creation of derivative works for
+commercial or non-commercial use with no legal requirement to release
+your source code. Other differences include Boost not requiring
+reproduction of copyright messages for object code redistribution, and
+the fact that the Boost license is not &quot;viral&quot;: if you
+distribute your own code along with some Boost code, the Boost license
+applies only to the Boost code (and modified versions thereof); you
+are free to license your own code under any terms you like. The GPL is
+also much longer, and thus may be harder to understand.</p>
 
 <p><b>Why the phrase &quot;machine-executable object code generated by a source 
 language processor&quot;?</b></p>