Depending on the game. Recently, I played Castlevania on DS and I spent about 2 hours a day at most, since I also work as an article writer.
Im playing 3 hours per day now, used to play over eight but i dont know whats the problem, boring new games or something else
5 years ago i spent 5 to 6 hours daily playing strategy games. But these day it hard to find time play games in 5 to 6 months.
More of a weekend gamer, but usually a few hours at a time. Love RTS and Tower Defense, and those are usually much longer sessions.