I’m busy writing the PM book, and saw these great posts. So instead of making myself crazy trying to write more good stuff for you, I decided you should read these.
What is managing software development? is a great read. BTW, the working definition I have of project manager is: the person who knows what “done” means and can steer the project to accomplish “done.”
Difference Between Planing and Scheduling talks about the difference. For me, project management planning is the identification of release criteria and other prose about the project. Scheduling is the WBS, whether that’s on yellow stickies or not.