I am considering two positions, one a formal PM job, the other a supervisory role within a functional organization. I have gotten the impression that people who actually hold the PM job title work many hours. One guy said he worked 80 hours straight once over Thanksgiving weekend to finish a project. Of course, the textbooks would say that unplanned overtime is the result of poor project management, etc.
EDIT: Let me rephrase, so that this question doesn't get closed: What's the average amount of weekly hours a project manager should typically put in? How can I tell if I'm being taken advantage of and am working too many hours?