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

[forevercloud3000]

I really think any game needs to have at least a 10-12hr campaign of sorts, with some replay value to warrent my $60 purchase. Vanquish, great game but too short for that price. MP is fine and all, but I am old school in the way of my games needing to be able to stand on their own single player experience in order to retain my attention. This is also why I skipped over gems such as Warhawk and MAG. Purely online experiences, by their nature are built to end. Plus, most games essensuate the deathmatch play style and I am not the greatest in those, instead I prefer more coop based multiplayer modes.

The DLC debacle is beyond annoying at this point. I was expecting full on expansion packs at the start of this gen, instead we are getting half a game, and the rest conveniently sold separately.