I like the people that play old 80's and 90's games and call themselves "hard core gamers". Though I do suppose they have a right to their own opinion.
To me, gamers are just laid back and play really whatever they like, and whilst they do this, they don't really care what other people think.
I'd consider myself a gamer, I've spent like, 350 playing TF2 on a comp, with about 125 hours in Dawn of war. A gamer to me, will talk about games from time to time, but not like;
"hey man, I got a random knife kill in cod"
"cool man! I ran over some guy in halo and right after that, I exploded"
"cool..."
"..."
"did you hear that new rush albem-"
*ahem. If you are hardcore gamer, great. If you're a casual gamer, cool. If you know a lot about a game, sweet. Just, don't let it take over your life.