The following is what I get when I drop a Flickr photo into my blogging software, paste HTML in, or try to post from Flickr:
a href="http://www.flickr.com/photos/51035715190@N01/3264441491"
title="View 'IMG_2448.JPG' on Flickr.com"img
src="http://farm2.static.flickr.com/1156/3264441491_7e5481fb04.jpg"
alt="IMG_2448.JPG" border="0" width="500" height="375" //a
All the angle brackets get stripped out.
This never used to happen before, with (mumble) Wordpress 2.03 on the old host, using PHP Markdown.
[UPDATE]
After some further research, it appears that Markdown is not at fault: it runs at rendering time and doesn’t change the contents of your database.
According to this blog post by Joshua Scott, lt; and gt; entities are being dumped when the content is posted through an XML-RPC gateway, like my blogging software, or Flickr’s “blog this” feature.
This appears to be a bug in one of the PHP XML libraries, which has been fixed in the latest CVS build, but requires libxml2-2.7.3 or higher.
Off to bug Joyent.
(Edited a bit to remove speculation about PHP Markdown and Wordpress XHTML options.)