XSReality have an interview with Lakerman, Swedish Quake god. Its interesting to note his profession is listed as "Professional Gamer". It covers a bit of his history and details his (impressive) earnings as a pro gamers.

As I said earlier I've been playing video games since I was 4, it's in my blood :). I think to become a good gamer you need a few things: You have to have talent, you have to be pretty smart, you have to think what your doing is fun, you have to love competing, you have to hate losing above anything else and you have to be able to perform well under pressure. I think most good athletes in any sport have most if not all of these qualities.

Those crazy Swedes! There's a whole stack of Swedish gamers and they all seem to be damn good.