In this scenario, timerFunc() is never called. What am I missing?
class AppDelegate: NSObject, NSApplicationDelegate { var myTimer: NSTimer? = nil
NSTimer's are not scheduled automatically unless you use NSTimer.scheduledTimerWithTimeInterval:
NSTimer.scheduledTimerWithTimeInterval
myTimer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: "timerFunc", userInfo: nil, repeats: true)