Whenever you go to play, whether it is on a console or handheld or PC, for how long do you usually play?  I used to play for about 2 hours at a tme but only have one session a day.   Now I find myself playing for somewhere around a half hour, but having 2 or 3 sessions a day.  So how long does everyone else play?

Probably around 3 hours.

Usually about an hour, one to three sessions a day. This is where handheld gaming comes in handy; no need to restart systems and whatnot.

Mine are typically pretty short these days (unless it's Tetris), I don't really have the time to game for hours on end anymore.

If i'm on vacation from college and only working, I usually play 2hrs a day, one session only (don't have time for more)
But now I'm working and in college, so I don't have the time to play, and that sucks!

It depends, what if I just bought a game I really wanted? Then I would play for like 10 hours straight.

over 30 seconds

depends if singleplayer or multiplayer and then with or without friends.

singleplayer, i would say 1.5-2 hours
multiplayer, i would say 1 hour
multiplayer with friends, i would say 2.5-3 hours

On weekdays, I can manage about 1h30 or 1h45 but during weekends I can game for 4-5 hours a day (if I'm home of course).

Well, it really depends on which game I'm currently into. My Skyrim sessions could go all the way up to nine hours (with nothing but food eating and bathroom visiting in between) on slow holidays. Playing Halo in matchmaking usually don't go past one hour and a half, while a campaign session may last throughout half the game (approx. four hours).

I guess the average would be somewhere around three hours, so that gets my vote.