1. People with JS disabled can’t read them
2. It’s bad for your website’s search engine rank (SEO) as the search bots can’t read them
3. It slows user’s browsers down (if only slightly)

I have written a very simple PHP script that pulls in your Twitter posts, and outputs them in an unordered list. Feel free to use however you like:

<?php
// Your Twitter username
$username = 'mikemike86';
$rssUrl = "http://twitter.com/statuses/user_timeline/$username.rss";
$rss = @file_get_contents($rssUrl);

if($rss){
	$xml = @simplexml_load_string($rss);
		if($xml !== false){
			$var=true;
			foreach($xml->channel->item as $tweet){
				//echo $tweet->pubDate."\n";
				echo ''.substr($tweet->description,(strlen($username)+2))."\n\n";

				if($var){
					break;
				}
			}
		} else {
			echo "Error: RSS file not valid!";
		}
	} else {
		echo "Error: RSS file not found. Username invalid or requires authentication";
	}
?>