For me its Strategy games
The first time I played Civilization 1 on the Amiga 500 it was pure magic.
Now I am waiting for Medieval 2 - Total War. It will be the game to end all games for me. Atleast until they make another one. Also been playing alot of Civilization 4 - though the new expansion was a big let-down. Also played Oblivion - I genuinly think that is a step forward - a true Next Gen game if you will, but that is another discussion for another time.
In the past I played Counter Strike alot - was in a british clan - we managed alright
But as has been mentioned to play that kind of game seriously takes up alot of time - so as responsebilities grew game-skills faded
Now for the real nail in the coffin - proving that I am a gamer - I met my wife through Star Wars Galaxies
She was a Twi'lek dancer and I was a trandoshian bounty hunter - a match made in heaven