Heh, to be honest it depends on who is going to read the application. Some people will think it's cool you have a hobby you're committed too and some will read it as you wasting your time hours a day on a stupid game.
Frankly though, if you can't get in where you are applying with near perfect scores; your collection of clubs; and two sports - listing Pokemon isn't going to help.
I'd pretty much have to agree with what Caelum said. It
does matter who reads it, and if they aren't so serious as to see this kind of thing written down, then I could see it for someone to see a whole different side to me.
It would definitely separate you from the rest of the asians (or whoever) have many things like that, because I have a few friends who have done pretty much what you've accomplished, so putting something like this in your essay, it'd give a twist to who you are.
I guess it's what you believe the reaction will be like. Best bet would be to know who is going to read your essay, and read that person with your eyes on how they act, and if they're serious, probs best not to add it, and if they have a sense of humor, then I don't see why not.
Putting something like that would be me putting down 'I'm a professional MTG player.' I doubt me coming in 2nd place in a national tournament in Seattle winning $175,000 smackeroonies would really get their attention. Considering that prize money is pretty much going to college funds anyways lol. Again, it's up to you, and it's really a 50/50 chance on whether they'll take you as a joke, or another person with a 4.0 GPA but just with a twist with a hobby not many others would have or enjoy doing.
If you ask me, if I wrote that down in my college essay, or even put down my success at MTG tournaments, it'd be a real awkward moment. If the person reading my essay sat down to talk with me, and didn't find it very well and saw it as me taking the College essay as some kind of joke, then I'd crap my pants lol.
~ Aether Nexus