I spoke a while ago with a friend about this topic, and she raised an example from the world of photography. Today, everyone and their grandma have a camera. Stores offer a wide selection of affordable cameras of all sorts, we've got cameras plugged in to our computers, and even got cameras in our mobiles. We've got cameras coming down our proverbial arses. All we need to do to take a photo these days is to take out our mobile and snap. Does that make everyone a photographer?
Some might say yes, if you take photos that makes you a photographer. I say: heck no!
There's a difference between taking a quick snapshot of your buddies on your mobile's camera to the craft, skill and dedication it requires to produce truly impressive, quality photos. There are people out there who truly care about the art of photography, who try to learn more about it and take part in it, not necessarily on a professional level. Are they to be placed on the same level of craft as some random person with barely enough skill to point the camera and click?
The same can be said of writers, artists, divers, boaters, mountain-climbers, skiers or whatever. Anyone can write, or draw, or get underwater, or go on a boat, or ascend a mountain, but few do it with the appreciation and dedication of true enthusiasts.
So why can't the same apply for gaming?
For me, the title of "gamer" isn't one of some pretended superiority, an exhibition of one's "uber" skill and achievements in some virtual world, or the devaluation of the "casual gamer". But it does mean something. It means an appreciation of the activity, perhaps a degree of enthusiasm to the medium as a whole. It means belonging to a unique subculture that the so-called gamers have formed around them. It says that "you may dabble in games from time to time, but me? I game.".
This doesn't mean to imply, at least not for me, that people who play gamers "casually" are any less than a "real gamer", or that this activity is some form of heresy, and that there is something wrong with it. Being a "gamer" is merely an arbitrary title that separates the dabbler from the enthusiast.