Change needed to get "Featured Image" working.

Using WordPress 3.6.1 & version of 1.3.3 of this plugin…

In this file: wp-facebook-like-send-open-graph-meta.php:

In this function: fblsogm_add_facebook_og_wp:

Line 441:

$catch_thumbs = wp_get_attachment_image_src(get_post_thumbnail_id($post->id), 'large');

I had to change $post->id to $post->ID or get_the_ID().

http://wordpress.org/plugins/wp-facebook-like-send-open-graph-meta/