Workbench Moderation and Custom Field Issue
Due to the underwhelming response, I had to figure it out for myself :-). To save any other newbie hours of angst, here is the solution:

As predicted, the answer was simple, but finding it was the problem! I eventually found how to load the latest revision by looking at the workbench moderation module source code. If you add the line under the $node variable assignation below, it will return the value on the current revision:

&lt;?php 

$node_id = arg(1);
$node = node_load($node_id);
$node = workbench_moderation_node_current_load($node); //NEW LINE!
$fieldname='field_approvers';
$items = field_get_items('node', $node, $fieldname);
if($items)
{
 $key = $items[0]['value'];
 echo "key = ". $key;
}
else
{
 echo $node_id;
}
?&gt;


Hope this helps someone.