Yes, the definition of girl gamer will change. Some. And society will too, some. Somewhat as a generational effect, as more people (men and women) grow up with games, the more "normalized" it will become. It'll be faster than you think. The switch from gaming as "nerdy" to "mainstream" has been less than 10 years, and gaining great steam. See also, social gaming, or "casual," this piece by Bogost is swell
http://www.bogost.com/blog/cow_clicker_1.shtml. If you don't think that will even out gender differences, then you're a dope because social gaming is changing the definition of "gaming." That's why we even have definitions for "hardcore gamers" and "casual gamers," which, like 3-4 years ago, were not prevalent. Wii and Rock Band and DS did a ton to change that (though tetris, minesweeper, and solitaire led the way).
But, women who game will always be sexualized. Why do I say that? Well, many men still give bonus points to women who: can drive stick, hunt, follow professional sports, camp, drink beer, etc. You know why? GUYS LIKE GIRLS WHO LIKE THINGS THAT GUYS DO. duh. So as long as a subset of guys like video games, those guys will continue to crush on girls that share that interest. Why does this have to be? Because women control access to sex, and thus will always be sexualized. The average woman has her pick of many potential partners, the average woman determines who she sleeps with. Women can chose to, or more often not, sleep with whichever guys that hit on her that she likes. Guys, on the other hand, are socialized (or biologically driven, as well), to get used to rejection, to get used to not having the last say in when sex happens. It's a supply/demand thing - guys are going to continue crave that for which they cannot have. Women cannot have control over whether sex happens or not AND whether guys lust. Both are mutually exclusive. So, until you all start becoming whores, men will still continue to crave you.
The more things change, the more they stay the same.