Tyler Cowen's post about what makes a game good got me to thinking about why there has long existed a difference in popularity of video/computer games between men and women, and what it would take to change that.
(Digression: of course, the Wii has made a lot of progress, and I've known women who started playing because of their brothers, but hasn't had the kind of addictive capacity it's had for men).
So see if my thinking is right here: a game becomes addicting because it stimulates your brain in a way that you want to get more of it. So, if games have historically appealed to males and not females, it must be because they have historically challenged a part of the brain that is more pronounced for men than women. Fortunately, brain researchers know exactly which areas these are: women have a more pronounced Broca's area and Wernicke's area, which are vital for the use and processing of language (damage to them can cause inability to coherently use language), while men have more pronounced brain areas for detecting motion (more specific names forthcoming).
So, for games to appeal to women in the same way that they have appealed to men, they would have to require you to notice and respond to subtleties of language -- perhaps you'd need to be able to infer mood, deception, hesitation, etc. from others' speech in order to advance. In other words, situate you in the middle of a Jane Austen novel in which you have to navigate human interaction with something like the same complexity that exists in human interaction.
And in fact, it does appear to me as if that attribute has been lacking in any game that's not online, and probably because it's so hard to program.
Just a thought.