Why won't my Instant Snapshot service show up in the iPhoto services menu?

I've followed all of the instructions on the "Mac 101: Automator" page to learn how to use Automator, but the service I make doesn't show up in the services menu on my iPhoto like the instructions page shows it should. I've tried following the instructions a few times to see that I didn't make any mistakes and I have tried restarting iPhoto. I've also tested the workflow on Automater and it works fine, the photos come up in my iPhoto. How do I get this "Instant Snapshot" workflow to show up in the iPhoto services?

This is the page of directions I followed: http://support.apple.com/kb/HT2488