How many hours should a single player game today be to warrant a sixty dollar purchase?

[ghettoglamour]

It depends if it's an intense linear game like Uncharted or God of War (then 10-12 hours are ok if the game's good) or if it's less intense but larger like Far Cry, Saints Row or Borderlands (20+ is a must). In fact, Borderlands 2 was too long for me to do all the side missions.