I don't consider myself to be a hardcore gamer in general. When I get into a game, I can get pretty obsessed, but those kind of big releases are getting few and far between. Bioshock was the last game I played religiously, and ESIV: Oblivion before that. That's a pretty wide gap. I don't play online at all, and you won't catch me waiting in line for 16 hours at the local Gamestop for the latest release of a console or blockbuster game.
I'd only consider myself a hardcore gamer when it comes to one particular series: Resident Evil. I'm a nut for just about anything Resident Evil-related. I've played and beaten every console RE game released in the States multiple times (including the dreadful Gun Survivor games), and I own at least 1 version of nearly everything bearing the RE name (the most would be 3 different versions for RE1 on PS1; original big box version, Director's Cut, and the Dual Shock re-release). I payed close to $100 for an unopened copy of the N64 version of RE2, despite the fact that I didn't have a working N64 at the time (and still don't). I picked up RE: Deadly Silence the day it was released... and I still don't have a DS. I even have a Resident Evil tattoo, with more planned. I'm not joking.