Several of the comments left by TUAW readers asked the same question, and it's so easy to do that I decided to whip up a quick tutorial showing how this works. You probably have a tool on your Mac that can do the job for you with just a few clicks, drags, and menu selections. iMovie is the perfect easy tool for creating full feature films (just kidding) from individual scenes shot with the iPhone 3GS video camera. Here's how to do it.
1) Email your iPhone movies to the computer that you'll be doing your editing on. Until Apple or a third-party developer determines a great way to copy video files directly from an iPhone to a Mac using Wi-Fi, this is the easiest way to copy these files. Instructions on how to email iPhone video can be found in my first post in the section titled "Sharing your video".
2) Launch iMovie on your Mac. I'm using iMovie '09, part of Apple's iLife '09 suite. You can probably do the same things I'm going to describe here with earlier versions of iMovie, or even with similar applications such as Windows Movie Maker on PCs. However, I like the changes that have been made to iMovie '09 that add better titling, special effects, and shake reduction.
3) In iMovie '09, select File > Import > Movies... Choose the hard disk where you wish to save the movie, select Create New Event (or if you're adding more video clips to an existing event, select Add to Existing Event), select the .mov file you wish to import, optimize your video file as "Large", select Copy files (this keeps your original copy intact), and then click Import. The screenshot below demonstrates the user interface for this process in iMovie '09. Since iPhone video files are usually fairly small and short, the import process is normally quite fast.
4) Now that the video has been imported, you can begin to play with it. To start off, you'll need to create a new project in iMovie '09 (see below). You can choose one of the built-in themes to make your video even more professional looking.
Update: A number of readers took issue with my suggestion that you email the video, since the iPhone does a lot of compression before sending. Instead, you may wish to use the following method:
1) Connect your iPhone to your Mac using the standard USB connection.
2) If iPhoto is set up to launch automatically upon the connection of a camera, it will open; if not, launch iPhoto.
3) Import the photos from the iPhone into iPhoto. One or more of these "photos" will actually be the .mov video files created by the iPhone.
4) Drag the movie(s) from iPhoto over to iMovie to import them into iMovie, then start your editing.
To see how the raw video featured in the original post looks after 15 minutes of cheesy editing, click the play button below.