Originally Posted by andrewjg
"Liking" the Product page sent no product image to Facebook (I tried with and without http://<?php echo $_SERVER['HTTP_HOST']; ?>).
This is because you are missing a single quote in your <head> area:
It should be:
<meta property="og:image" content="http://<?php echo $_SERVER['HTTP_HOST']; ?>[product.image tag='0']" />