In later versions of CS10.0 a secure token is required for logout. This snippet can be placed in the appearance header to extract the logout link and execute it.

CS10.0 Logout Link

<script>
	$(function($) {
		$('.rhSingleClickLogout').click(function() {
			var onClickStr = $('#ToolsGlobalMenu a[onclick*="ll.DoLogout"]').attr('onclick') + "; onclick();";
			eval( onClickStr  );
		});
	});
</script>

<a href="#" class="rhSingleClickLogout">Logout Now</a>