It really, really varies. I spend maybe 15-30 minutes most days playing Pokemon shuffle. Otherwise, most days I don't game much. If I do decide to play a PC game, though (which happens once a week or so), I'll play for at least 8 hours. I get super into it. I'll forget to eat or shower, and then it'll suddenly be 2AM. I tend to avoid having days like that too often, as those are the days I contribute absolutely nothing to society.
It's difficult for me to narrow down how much time I actually spend playing. I'm a Computer Science major so I do spend quite a bit of time working on school related projects on my PC. I have a lot of friends over Steam and BattleNet who I will converse with while I'm working, and I'll take breaks from work with a game here or there. Overall, I would say I spend about 2 hours a day gaming, and another 2 hours idle but still logged in.
I'd say I spend about 1-2 hours a day gaming. I do go through spurts though. I work nights and watch my son during the day, so sometimes I'll play all day while he's awake, and other days I won't play at all. It also depends on how good my son is being too. Now that think about it, they're are several factors involved that decide whether I play for a certain amount of time.
I used to play more than 6 hours a day but I felt it was too much and was really affecting my health and relationships, so I tried to tone it down, and I managed to do so and I've been happier now than before.