Upgraded: Blog Title now won’t show in Browser Title tab…

I know that this is very simplistic in nature and I’m glad since I normally end up having major fixes. I just upgraded to 2.3 and the title of my blog doesn’t show on the main page: https://spiewgels-labyrinth.com/blog/

I checked with the previous version that I had and the header.php file is exactly the same and I can’t figure out why the title doesn’t show. However, each of my post pages show their titles accordingly…I’m just having a problem with the main page. I even tried using other function calls such as php bloginfo but it just seems that it’s not working. This is what my header file says:<title><?php wp_title(''); if (function_exists('is_tag') and is_tag()) { ?>Tag Archive for <?php echo $tag; } if (is_archive()) { ?> archive<?php } elseif (is_search()) { ?> Search for <?php echo wp_specialchars($s,1); } if ( !(is_404()) && (is_search()) or (is_single()) or (is_page()) or (function_exists('is_tag') and is_tag()) or (is_archive()) ) { ?> | <?php } ?> <?php bloginfo('name'); ?></title>

I’m using the 300 theme. Like I said, all the other pages show the title fine, just not my home page. Any help I can get will be appreciated.