"A project manager is a professional in the field of project management. Project managers have the responsibility of the planning, procurement and execution of a project, in any undertaking that has a defined scope, defined start and a defined finish; regardless of industry. Project managers are first point of contact for any issues or discrepancies arising from within the heads of various departments in an organization before the problem escalates to higher authorities.
Project management is the responsibility of a project manager. This individual seldom participates directly in the activities that produce the end result, but rather strives to maintain the progress, mutual interaction and tasks of various parties in such a way that reduces the risk of overall failure, maximizes benefits, and minimizes costs." - Wikipedia
I am more of a Project Leader than a project manager to be honest. That means that for me the people are the most important metric in the project.