When I was on air, I had to dress in slacks and a button down. And when I moved to the newspaper graphics department it took me a while to get used to dressing in jeans and t-shirt... which lasted until the new boss (picture Michael Scott from the Office, with more attitude and less aptitude) said we had to cut the jeans and dress up... Smart or Business Casual was what the official notice said.
Although, the managers only enforce it on certain people, when it suits them. I, for instance, am singled out on a regular basis and blamed for a fair amount of things that either aren't my fault or a mistake that everyone has made... so I don't dare not follow the dress code, whereas the woman who works at the next desk over wears capris and flip flops (both officially forbidden) and nothing is said. I wore dress jeans once and got called out on it. My immediate boss still goes barefoot even after being told not to.
...so that's my dress code. And my rant. I work and think better (eg, more creatively) when I can dress comfortably, so given I don't have to deal with the public I'm against it. It's not like I ever dressed sloppily anyway.