Competitive atmosphere, you'll go as far as your skills and ambition will allow. No free rides or automatic promotions.
Pros
Stock options are not overly generous, but the company is public and they do tend to pay off, mostly. Products sell themselves. Collegial atmosphere. Freedom to experiment, make mistakes. I've seen talented people go from individual contributor to Senior director and even VP. You may hire in at a particular level, but promotions are not automatic or guaranteed. This leads to quality in management.
Cons
Career paths not clearly defined. Due to lack of automatic promotion, career paths have been put on paper, but no one is guaranteed anything. If you are not interested in being a shareholder, there are other places you should probably look for a job. Few frills. Fluid management structure. Since the company is public, it is possible that a particular persons stock options will not be immediately valuable due to market fluctuations. Management is frugal in spending, so don't expect lots of trips to Europe in first class at top rated hotels for junkets.
