Since you are using the button_count layout, there is a little trick I found that seems to work. Basically you just wait for the iframe to be inserted, and then set its width to 0. It will then automatically resize itself to the proper size. I can't swear this works under all circumstances and with all widths, but please test it out and see if it works for you. Here is a sample code page:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<script type='text/javascript'>
function loadcode(d, s, id)
{
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) {return;}
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/all.js#xfbml=1";
fjs.parentNode.insertBefore(js, fjs);
}
function init()
{
loadcode(document, 'script', 'facebook-jssdk');
setTimeout(initx, 10);
}
function initx()
{
likeframe=document.getElementById('d2').getElementsByTagName('iframe')[0];
if (likeframe) setTimeout(setwidth, 10);
else setTimeout(initx, 10);
}
function setwidth()
{
likeframe=document.getElementById('d2').getElementsByTagName('iframe')[0];
likeframe.style.width='0';
}
</script>
</head>
<body onload='init()' style='margin:10px 50px'>
<div id="fb-root"></div>
<div style='text-align:right'>Here is some right-aligned text to compare to.</div>
<div id='d2' style='float:right'>
<div class="fb-like" href="http://www.google.com" data-send="false" data-layout="button_count" data-width="90" data-show-faces="false"></div>
</div>
</body>
</html>
Unfortunately this doesn't work for the standard layout, not sure why it's so different.