Sheesh! We've got a 73-year-old grandmother in our gaming group. She plays Guild Wars, dabbles in WoW, and her grandkids got her hooked on Half Life 2. Another member of the gaming community has his own family CS clan, with his sons, his wife, his father, and his grandfather playing. I think there's a console-gamer granny in the Cleveland area who plays shooters on the xbox. She's been profiled in the local paper.
A growing number of gamers are over 40, and even over 50. These are the people who were in their 20s when the PCs and early game consoles came out. Not all of them want to play Solitaire or Bejeweled!