Cant claim my steam games have been played as much as some of the others here. Got many hours on other games, but steam games seem to be quite low.
Top 4:
Mass Effect 2: 67.3h
Mass Effect: 49.7h
KOTOR: 48.6h
Recettear: 33.2h
Not too impressive nope. But i generally play though a game once, finding every secret and stuff, then i start another, with few exceptions.