Watch out! This tutorial is over 8 years old. Please keep this in mind as some code snippets provided may no longer work or need modification to work on current systems.
Include the post thumbnail in your RSS feed.
// Put post thumbnails into rss feed
function itlc_feed_post_thumbnail($content) {
global $post;
if(has_post_thumbnail($post->ID)) {
$content = '' . $content;
}
return $content;
}
add_filter('the_excerpt_rss', 'itlc_feed_post_thumbnail');
add_filter('the_content_feed', 'itlc_feed_post_thumbnail');