04-20-2009 09:05 AM
Thanks for asking this question as others may have the same. The icons you are seeing (with the exception of FM) are earned based on the number of posts a user makes or questions a user answers. There are many layers of advancement opportunities so please don't be shy to ask your questions or reply to posts.
The FM icon denotes the "Founding Members" of the forum. They have contributed content that is and will be valuable to users as the forum becomes more well known.
Thanks again for asking!