An alt attribute has been added to your Twitter link in header.php. Change:
<div id="surheader">
<p><img style="vertical-align:-3px;" alt="Twitter" src="http://www.radicalcontrapositions.com/left_flank/wp-content/themes/panorama/images/twitter.gif" height="16" width="16" /> <a alt="Left_Flank" href="http://twitter.com/Left_Flank">Left Flank on Twitter</a> | <img style="vertical-align:-3px;" alt="RSS" src="http://www.radicalcontrapositions.com/left_flank/wp-content/themes/panorama/images/feed-icon-16x16.gif" height="16" width="16" />
to
<div id="surheader">
<p><img style="vertical-align:-3px;" alt=" alt="Twitter" src="http://www.radicalcontrapositions.com/left_flank/wp-content/themes/panorama/images/twitter.gif" height="16" width="16" /> <a href="http://twitter.com/Left_Flank">Left Flank on Twitter</a> | <img style="vertical-align:-3px;" alt="RSS" src="http://www.radicalcontrapositions.com/left_flank/wp-content/themes/panorama/images/feed-icon-16x16.gif" height="16" width="16" />
I spoke too soon. That change did nothing.