Here's what I did (with some help from a friend over at vBulletinsetup.com :up: ) to have it shown to the right of the title portion of the message area rather than the postbit....
Code:
<span style="float: right;" class="smallfont"><script type="text/javascript">
tweetmeme_style = 'compact';
tweetmeme_source = 'TheWDBoards';
</script>
<script type="text/javascript" src="http://tweetmeme.com/i/scripts/button.js"></script></span>
....I like the way that it displays in the message area with the compact button!