>Who does what, who solves which problems
Indeed very important. I don't like to call it networking, because that always sounds like being overly nice to people you don't like, but getting to know the people who can help you out is a major factor when you arrive at a new job. Also: Don't be a smartass, and don't try to push your opinion on things too hard, even if you know you're right. Companies might act like they want it the other way around, but in my experience companies prefer people who don't cause a ruckus - no matter how noble the intentions were. So try to integrate without causing your coworkers or your boss any trouble, and when you have a few years of experience and made a name for yourself, then you can still bring in your own ideas and do things your way.
Also: Don't be scared of how good everyone might be. You are always clueless when you are new at work, even with experience. 12 years or so ago I thought I'll never make it, because everyone else was so good at their jobs, but now 12 years later I can see how everything is just a collection of skills you naturally acquire over the years, nothing magical to it.