Well, i see there are lots of different opinions of the term.
Regarding the game's complexity, many of todays genres that are considered suited for hardcore gamers actually pretty casual. I can easily get into mostly any FPS or 3rd person shooter in a very short timeframe. For RPGs, adventures or strategic games there is really some time to get into the method of playing the game, but even for many of them the learning curve is pretty easy to master (maybe the most complex are strategy games where you need to learn about various units and stuff).
Regarding graphical complexity, i don't see why more graphically complex game should be more hardcore. For me, graphics are only meant for making the game more immersive(also depending on type of the game).
As for controls complexity and the time and dedication needed to master them, it seems that currently wii games like SSX blur are the most hardcore games out there :) Pretty much everybody is used to D-pad, and analog sticks are a no-brainer either, and some of the most control complex games i encountered on PS2 are PES games, and for PC good old helicopter simulations. This also rules out many of the games and genres considered to be hardcore.
So, this breakdown of complexity would pretty much kick out FPSes as a hardcore game genre, and there is a general opinion that xbox360 is pretty much about them.
llewdebrkram said that his son considers himself a hardcore gamer because he reads all about latest games and only plays games like GTA, saint's row, RE and so on.
If that was the criteria, i would easily be able to consider myself harcore gamer (atleast till some 5 years ago or so), but i still consider myself casual gamer, even if i played/finished all of the sequels of GTA (including the first two, i haven't played london tho).
I just think that term of a hardcore gamer today is tied to a population of players(mostly of teenage age) who enjoy immersive gaming experience which, even if not realistic, should be visually and interactively persuasive as possible.
.
