FB Sharing for WP by Chad Von Lind, get_the_excerpt() trunc

<!-- Begin FB Sharing for WP by Chad Von Lind. Get the latest code here: http://vonlind.com/?p=539  -->
    <?php
        $thumb = get_post_meta($post->ID,'_thumbnail_id',false);
        $thumb = wp_get_attachment_image_src($thumb[0], false);
        $thumb = $thumb[0];
        $default_img = 'http://www.maskc.org/img/logo/MASKC.jpg';
    ?>

    <?php if(is_single() || is_page()) { ?>
        <meta property="og:type" content="article" />
        <meta property="og:title" content="<?php single_post_title(''); ?>" />
        <meta property="og:description" content="<?php
        while(have_posts()):the_post();
             $excerpt_truncated = get_the_excerpt();
             if ( strlen(get_the_excerpt()) > 274)
             {
               $excerpt_truncated = substr(get_the_excerpt(), 0, 274)."...";
             }
        $out_excerpt = str_replace(array("\r\n", "\r", "\n"), "", $excerpt_truncated);
        echo apply_filters('the_excerpt_rss', $out_excerpt);
        endwhile;   ?>" />
        <meta property="og:url" content="<?php the_permalink(); ?>"/>
        <meta property="og:image" content="<?php if ( $thumb[0] == null ) { echo $default_img; } else { echo $thumb; } ?>" />
    <?php  } else { ?>
        <meta property="og:type" content="article" />
        <meta property="og:title" content="<?php bloginfo('name'); ?>" />
        <meta property="og:url" content="<?php bloginfo('url'); ?>"/>
        <meta property="og:description" content="<?php bloginfo('description'); ?>" />
        <meta property="og:image" content="<?php  if ( $thumb[0] == null ) { echo $default_img; } else { echo $thumb; } ?>" />
    <?php  }  ?>
<!-- End FB Sharing for WP -->