As of WP 3.3 this is the preferred usage. Thanks to Henry C. Gernhardt, III and Martin Lormes for reporting this issue.
…et_template_directory and get_stylesheet_directory functions.
…et, rather than output broken markup.
… internally by comments_template, we don't need to duplicate that logic.
…and pass int the correct one when initialising it.
…is set to true.
…ring bugs experienced in Safari 5.
… Thanks to Martin Lormes for suggesting this.