My twitter feed does not work anymore as of 12.06.2012
Twitter stopped using old API, in order to have have your twitter feed working you must to the following steps.
1. Make a backup of your class.shortcode.php file located in Clapat folder of your current Eleven-WP Theme Installation
2. Edit class.shortcode.php with your favorite text editor (recomanded notepad ++), find function twitterFeed - for 1.2 version starting from line 15 till line 77
3. Replace those line, with the content from attached .fix file. - http://clapat.ro/themes/eleven-wp/fix.txt
4. Upload the modified file and hard refresh the page. (CTR+F5 for Chrome)