Whether it's being usurped by a younger, more dynamic playmaker or being cast aside as a new regime moves into power, the quarterback carousel keeps on spinning. With a deep, albeit unspectacular crop of quarterbacks in the Draft, and eight head coaches being fired, that carousel will undoubtedly spin a little bit faster this off-season. With a couple of exceptions, each new coach is going to want to crown a new field general to lead his team. And even some incumbents will be looking to upgrade at quarterback in an effort to save their jobs, and avoid Black Monday, the 2013 edition