I work at a pretty conservative company, and even I wish salaries were open, at least internally. I don't believe that salary should be determined by how effective of a negotiator you are, but rather what your skills are worth to the company. If you knew they were low-balling you compared to your coworkers, how would you feel?

I wish job postings more often had salary information, too. How am I supposed to know if an interview is worth my time when I don't know if the pay will be higher or even competitive with what I'm making now?