I think NYTs links don't last too long, so I'll quote some key nuggets here in case you can't get to the article later:
...the women of St. Mary are actually part of a vast and growing community of video-game-playing baby boomers and their parents, especially women.
Anxious about the mental cost of aging, older people are turning to games that rely on quick thinking to stimulate brain activity.
It turns out that older users not only play video games more often than their younger counterparts but also spend more time playing per session.
“Women come for the games, but they stay for the community. Women like to chat, and these games online are a way to do that. It’s kind of a MySpace for seniors.”