Good question. My answer is just a theory. Many members here do not know that they have the option of adding their location to their profile.
This can be done by clicking on the profile button on the menu above this page. This will take you to your profile page (if you are logged in). Then select "Profile Information" from the menu and fill out whatever you can to add to your profile. The field for location is under the birthdate field.
I have now changed the layout on the forum so location can now be shown to the left of the member's post.
If you just have Location: with no city, state, country, etc., to the left of your post (see under my avatar) , it means you have not added the location to your profile.
And.... of course, if you want to keep the location a secret, that is also your choice.
In your profile information, you can also add your own picture (avatar, Personal Text, Birthdate, Gender, ICQ number, AOL Instant Messenger nickname, Your MSN messenger email address, Your Yahoo! Instant Messenger nickname and a signature that will be displayed at the bottom of each post or personal message. BBC code and smileys may be used in your signature.
Try it out and please ask if you need any assistance.