I always try and dress nice, its funny walking into a room with 5-6 other people trying to get the job and there in street clothes and your in something all slick, it makes you feel superior and usally the person hiring will take notice.

Now im not saying street clothes is not ok, ive actually gone to a 2nd interview in my street clothes because the first one i knew i got the job so basically the 2nd one was getting my info for the job like when to start and what not, it was funny cause my then boss said just dont wear those sandles ok.