Is the table centering? Try text-align: right in your div and get rid of the margin:0 auto in your table tag.
Yes, the centering is fine. I just can't get it to right-align. I tried what you suggested (below) but it won't right-align in Firefox:
<div style="text-align:right;">
<table border="1" style="width: 50%;">
<tr>
<td>cell</td>
<td>cell</td>
<td>cell</td>
</tr>
</table>
</div>
I can get it to right-align as below, but it only right-aligns in Firefox that way:
<div style="text-align:-moz-right;">
<table border="1" style="width: 50%;">
<tr>
<td>cell</td>
<td>cell</td>
<td>cell</td>
</tr>
</table>
</div>
The -moz-right is also flagged as invalid CSS in my code editor. The closest I've gotten so far is to try to display the table inline as below, but it makes the table look weird.
<div style="text-align:right;">
<table border="0" style="width: 50%; display:inline">
<tr>
<td>cell</td>
<td>cell</td>
<td>cell</td>
</tr>
</table>
</div>