Have you seen my blog sidebar? I display the number of followers I have in full text. This is actually pretty easy to do. The first thing you need is this function:

function get_followers($twitter_id){
	if (preg_match('/followers_count>(.*)</',$xml,$match)!=0) {
		$tw['count'] = $match[1];

	return $tw['count'];

Once you have the function, you can call it as shown below:

$nb =  get_followers('phpsnippets');
echo "PHP Snippets already have ".$nb." followers!";