I just noticed that if I log out of the forums, any users that are currently logged in and are on my buddy list are still shown in blue, whereas users that are not in my buddy list are shown in the standard red. This would seemingly mean that I am still identifiable as “me”, as the “blue” users are in a buddy list associated with my login, despite my current status of “Logged Out”.
As a follow up, I disabled all cookies, logged out and logged back in, just in case it was caused by a per-session cookie, but the buddies were still in blue when I restarted the browser.