It includes 30 some tutorial sessions, each about 5 minutes long. You watch these, and you will be amazed what you can do with iMovie.

http://itunes.apple.com/us/app/tutor-for-imovie-11/id416624070?mt=12

As you say Tom.......I have really enjoyed the videos and editing work that Justin, Drake, Greg and others are doing. I am also amazed how good the camera is in the newer iPhones.
For example, I have been using a App called Track ADdict HD on my iPhone. And during autocross events, using rubberbands to secure my iPhone to the rearview mirror of my Mini.

The App can be set-up to begin to record the course the intant that it recognizes movement of the iPhone. And while the car is on the course, recording the speed and g-force in the turns. When you see the video on the iPhone, it really shows off the quality of the video. When compressed into a youtube video, it looses some of its quality, but still pretty good.

http://www.youtube.com/watch?v=ePOTz9X6ttk

Joe