I find I rarely need to target any browser other than IE with specific styles, so I usually end up doing something like this, which doesn't rely on JS.

   <!--[if lt IE 7]><html lang="en" class="no-js ie ie6"><![endif]-->
   <!--[if IE 7]><html lang="en" class="no-js ie ie7"><![endif]-->
   <!--[if IE 8]><html lang="en" class="no-js ie ie8"><![endif]-->
   <!--[if IE 9]><html lang="en" class="no-js ie ie9"><![endif]-->
   <!--[if (gt IE 9)|!(IE)]><!--><html lang="en" class="no-js"><!--<![endif]-->

Edit: And then remove the 'no-js' class with js