I don't use Dropbox for audio, video or photos, and I'm already using more than 3.3G. A lot of my folders are probably things I put in there to quickly share it with someone or access it from another computer. I could move them now and free up some space. But, I can't be bothered. That's one reason why people will convert to premium. The hassle of sorting through folders is probably not worth $100 to many.