Actually it's impossible. > Display Name > Unique ID > Custom/Halo Avatar > Join Date > Follower Count > If you personally "follow" the member Any of these are quick indicators of detecting "impersonation" of other users. The best part (that I love) is that you can find out most of this information by simply clicking on a users display name that gives you an information box about their profile (without even visiting their profile page). Unique ID's are Unique among all members here. No two can be alike. Now with the new follower system, say I follow the "real" account. When I click on their display name, I get a checkbox next to "followed" indicating I follow them. If the said impersonator doesn't have that, than obviously they aren't who they say they are. Do what you want, but it's actually incredibly easy to distinguish "fake" accounts from "real" ones.