Related posts with Fb Like and Tweet button.

related_posts_via_tags.php

<?php // don't imclude this php tag

function make_related_posts() {
if(is_single()) { //to only show this on single posts view
$orig_post = $post;
global $post;
 
$tags = wp_get_post_tags($post->ID);
if ($tags) {
$tag_ids = array();
foreach($tags as $individual_tag) { 
	$tag_ids[] = $individual_tag->term_id;
}

$args=array(
	'tag__in' => $tag_ids,
	'post__not_in' => array($post->ID),
	'posts_per_page'=>3, 		//Number of Posts
	'caller_get_posts'=>1 		//To Ignore sticky post
);

$my_query = new wp_query( $args );
if( $my_query->have_posts() ) {
echo '<div id="relatedpostscover">';
while( $my_query->have_posts() ) {
	$my_query->the_post(); ?>
	<div class="relatedpostscontent">
		<div class="relatedpostspic">
			<?php
			$first_img = get_first_image(); //call to function fetching first image of post
			if($first_img != '') {
			?>
			<a href="<? the_permalink()?>" title="<?php the_title(); ?>"><img src="<?php echo $first_img ?>" /></a>
			<?php
			} else {
			?>
			<a href="<? the_permalink()?>" title="<?php the_title(); ?>"><img src=" XYZ " /></a> // replace XYZ with path of your default image
			<?php
			}
			?>
		</div>
		<div class="relatedpoststitle">
			<p class="rps_title"><a href="<? the_permalink()?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a></p>	
			<p class="rps_date"><?php the_time('M j, Y') ?></p>
		</div>
		<div class="relatedpostsshare">
			<span id="fb-button">
				<iframe src="http://www.facebook.com/plugins/like.php?href=<?php echo urlencode(get_permalink($post->ID)); ?>&amp;layout=button_count&amp;show_faces=false&amp; width=450&amp;action=like&amp;colorscheme=light" scrolling="no" frameborder="0" allowTransparency="true" style="border:none; overflow:hidden; width:80px; height:22px; position: relative; top: 2px;">
				</iframe>
			</span>
			<span id="tweet-button">
				<script src="http://platform.twitter.com/widgets.js" type="text/javascript"></script>
				<a href="http://twitter.com/share" class="twitter-share-button"
					data-url="<?php the_permalink(); ?>"
					data-via=" XYZ " //replace XYZ with your official twitter username
					data-text="<?php the_title(); ?>"
					data-related=" XYZ " //replace XYZ with your Site Name
					data-count="horizontal">Tweet
				</a>
			</span>
		</div>
	</div>
	<? 
}
echo '</div>';
}
}
$post = $orig_post;
wp_reset_query();
}
} 

//famous catch_that_plugin snippet in action

function get_first_image() {
  global $post;
  $first_img = '';
  ob_start();
  ob_end_clean();
  $output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches);
  $first_img = $matches[1][0]; //path of first image occuring in the_content
  return $first_img;
}
 
add_action( 'genesis_after_entry','make_related_posts' );