I changed the code a little by editing it above and you may have missed my changes, make sure you're using this line:
switch ($category[0]->term_id) {It's better to use the IDs if you can, in case you change the category names down the line.
Make sure you don't have two "Wordpress" categories set up. That would cause this problem because each would have a different ID.
To troubleshoot this, it may be necessary to output the category for each article so you can see why you're getting odd results.