New styles need to be added after the original styles if you want to overwrite them.
<iframe src='http://embed.verite.co/timeline/?source=0AubTk6Ov6UrIdFFYakFfZ2R6Q0VqWlVRNUFVX1E&maptype=toner&lang=en&height=650' width='100%' height='650' frameborder='0'>
</iframe>
<style>
.vco-storyjs h2.start { font-family: Verdana !important; }
</style>
<script>
jQuery(document).ready(function($) {
$('.vco-storyjs h2.start').css('font-family','Verdana !important');
});
</script>
Thanks! Loving the timeline - very cool.