Well I am both an online gamer (SWG for around a year and a half, but have since given it up) AND a table top gamer (Shadowrun FTW). Then again, I also watch NFL a great deal, and have known other gamers who were sports fanatics. I do find it odd that at work, if I start talking about my Elf Phys-Ad I get about the same amount of blank stares and questioning glances as if I mention Vick's rushing yardage in my gaming group. Then again, my "scenester" friends look at me funny if I mention either. And I'm pretty sure, depending on the pretention level of the club, the only reason you don't get burnt at the stake is because they may take you playing D&D as ironic, and therefore, cool. I am pretty sure if I started talking about the feats I took for my 18 level samurai/iujitsu master and the bonuses to dueling I got, I wouldn't be taking home that waifish tatooed vixen with the sweet ass.
Strangely enough, I didn't start table top gaming until college. All throughout highschool I stuck to being a music and film geek, with some video games thrown in for good measure. But yes, as said before, I think it's the combonation of math and statistics skills mixed with the roleplaying/improv that pins gamers as geeks. I mean, seriously, have you seen the Shadowrun players handbook? It's around 350 pages long, and you most people don't wait around for you to look up everything you need to play the game. I mean, look at how esoteric the combat system is:
1. Roll the number of dice in your combat skill, with any additional combat pool dice you would like (remember to save some for attacks against you) at the target number designated by the game master.
2. For the defender, subtract you armor level from the strength of the attack, this is the target number for you soak.
3. Roll you Body pool combined with any additional Combat pool you have remaining.
4. After negating attack success with soak success, use additional successes to stage the power of the attack down, hopefully taking no damage.
Did that make any sense to you? That's just normal combat, and that happens a whole lot. So yes, it is almost required that you be a "geek" who has been previously identified as someone with an obsessive knowledge of useless information and trivia.