Ya I always wear a pair of walkshorts (cotton shorts) and a nice woven or T and its just fine. Through on some shoes and we are golden. I have yet to wear jeans. Its basically like everyone else said just don't be a slob.
All the pics I see of Sweet, people are dressed REALLY nice. Now there are two factors...it's pretty chilly at night right now, it's not Spring Break. It's a "sweet" place, but they may relax the dress code for SB. Not sure though.