If you have your own install of WordPress, it's easy to make an iPhone-optimized theme for your blog -- without changing anything for non-iPhone users. This info might be useful for anyone building web sites with other tools as well. Here are the quickie instructions:
<?php
$iphone_stylesheet = str_replace(".css", "_iphone.css", get_bloginfo('stylesheet_url'));
?>
<link media="only screen and (max-device-width: 480px)" href="<?php echo $iphone_stylesheet; ?>" type="text/css" rel="stylesheet" />
<?php
if (strstr($_SERVER['HTTP_USER_AGENT'], "iPhone"))
{
echo ‘<meta name="viewport" content="width = 320″ />';
}
?>Mac OS X Hints
http://hints.macworld.com/article.php?story=20070709102837827