I thought I would get in on this argument, since it seems for whatever reason a topic people enjoy reading about. The points being made come down to is the way someone acts, behaves, or presents themselves show the way that person is in real life.
So is that guy who ninja'd your loot the type of person who would cut you off in traffic and not care about the results? Is that raid leader who can organize people with efficiency someone who manages people in real life? Is the person that is "too good" to move out of fire quick enough that lazy person who gets everyone to do everything for them?
Now I assume you all can see the similarities between the way some people who act in game or preform that matter, but many of them arguments people are making avoid one important aspect. Playing an online game such as WoW gives that person an opportunity to not showcase themselves or prove they can be something else. So maybe some people are sick and tried of getting bossed around at work all day come home and let it loose. Meaning they use the focus of I can do things better than my boss, watch and see. Or maybe the opposite. I spend all day focused doing all the crap I need to get done, I am going to come home and enjoy myself. Completely not giving a crap how it effects anyone else. This would be "it is a game" relax attitude we see a lot of the time.
Of course if someone is very introverted out in the real world they could use the online experience to let themselves loose. Have a field day and prove in this environment they can thrive because there is no consequences. Now I would argue you don't generally see the opposite a very extrovert person becoming the calm quiet one in the corner. So you could argue that those acting that way in game generally are those type of people out in the real world.
So what am I saying really? Well, people who play this game may use their real life skills and abilities to enhance their game play. This is true and why wouldn't you? Using what you can do well, to do better. No one wants to fail, at least no one I have ever met. Also people may use this game as an escape to prove they can do what they are not supposed to be able to do. So that guy who flips burgers could be your raid leader, or that guy who can't get out of the fire could be an very sucessful executive.
I am no sociologist, but I would expect they would see it from my point of view. When people are given an opportunity in a new society to be whatever they want. They will
a)Without knowing tailor themselves to who they are
b)Try to be something completely opposite
I really doubt there is middle ground. You are either an amplification of yourself or someone completely different. I am also not sure if I even made a point at all, but I am sure you all will tell me.