As stated in the announcement, if you're running FC6 or later, here's how to do this:
Open a terminal, enter:
su -c 'yum install smolt'
Enter root password when promted.
Once package is installed, enter:
press y when promted.
Your smolt ID can be useful in many ways. Like when reporting bugs in bugzilla, refer to it to give the developers an overview of your hardware. Here in FedoraForum, it can be useful when asking questions related to hardware, simply post your smolt ID and other users can look at it. Having a link to your smolt Hardware Profile in your signature might be a good idea.