Flickr is cool because many of the pictures there have the EXIF data for each picture listed.
for example, the picture below was taken under the following conditions:
Camera: Canon EOS 30D
Exposure: 0.001 sec (1/1250)
Aperture: f/6.3
Focal Length: 400 mm
ISO Speed: 200
You can see the jet is pretty crisp, but the sailboat masts have some slight blur from the panning. The jet is coming more head-on here, so there isn't so much panning action as the original IotD photo at the top of the thread, where the jet is flying by. The
large version of the image really shows this.