If you have the ckeditor wpgallery plugin enabled you can add captions to images. By default these captions are also links in the following format:
<a title="" href="http://www.flailingmonkey.com/2013/01/21/install-django-justhost-2/frustrated_developer/" rel="attachment wp-att-585">blah</a>
This link is picked up and processed by http://www.flailingmonkey.com/wp-content/plugins/ckeditor-for-wordpress/plugins/wpgallery/plugin.js?t=CBDD line 254, which results in matches being null. The pattern wp-image-([0-9]+ expects wp-image-585 and does not match wp-att-585, which results in match throwing an exception causing this issue.