Good news everyone! We have enabled the ability to show your Faction allegiance (including Mercenary and Lone Wolf) in your forum profile, which just so happens to be your user portrait! Changing it is simple, and merely requires you to log into your forum profile, and click on the 'Select Allegiance Icon' text over the currently blank portrait. Then you select the image, and confirm your choice.
And now you're done! We look forward to seeing you all - whatever your allegiance - on the forums.