[Lynne]

Kirby's code is a bit off... it should be <else />, not </else>. But you can use a condition around any of the table column classes you want to change. It may be easier to 'read' if you do it this way:

<if condition="is_member_of($post, X)">
<td class="whatever">
<else />
<if condition="is_member_of($post, Y)">
<td class="whatever2">
<else />
<td class="alt1">
</if>
</if>

You'll need to do that for every td tag you want changed.