Technically it's very easy.
CAMERA:
Set your camera up in a place where it won't move. Then either have a friend click the shutter or else set a timer for the shutter on your camera (usually 10 seconds). Or if you're going to use a built-in computer camera (like an iSight) then just sit right in front of your
computer and click the shutter yourself.
CREATIVE PLANNING:
One of the aspects of the production that makes that YouTube video look "fast-moving" is the fact that the lighting changes very distinctly with each image. If every shot was taken with the same lighting, then it would seem more smooth.
VIDEO PRODUCTION:
All you need to do after you've taken all your photos is to string them together into a video. I don't know iWeb very well, but I'm pretty sure you won't be able to do this with that software. You might want to explore some video editing software... I recommend using Quicktime Pro (it's very inexpensive -- $30). With Quicktime Pro you can assemble the images into a sequence and overlay an audio track. Then you can also export the finished video file in a variety of formats and get it up onto YouTube.
