I'm using the AWH template and have one listing that references another in the body of the listing main review. This has caused a "trackback" which seems to be in the database as an approved comment, but it doesn't appear back on the referenced listing. How do we get trackbacks to show? The same problem will happen if someone on another blog posts something about any one of my reviews.

Trackbacks don't really fit in with review sites. Usually you want people to be focused on clicking your affiliate link, not going out to another site that may take the commission.

They're explicitly hidden in the comments.php file of the theme.

But if trackbacks are enabled you can't stop people from commenting on their blogs about it. So I guess the tradeoff is either leave them on or turn off trackbacks. It comes down to if the incoming link juice minus outgoing traffic plus confusion of invisible comments is worth it. I'll leave them on for now and see what happens - comments can always be made unapproved. Thanks.