I stay logged on Facebook since this is my computer so I don't have to share or anything. How much I go on it, maybe like 5-15 minutes total a day. I do a daily thing on one of the games, check if I have notifications, maybe check the Hunger Games/Glee/Lady Gaga/Taylor Swift page and look a bit at my news feed - and that's pretty much it.
I use it every day, but I stay on it for brief periods. I message people up there alot, and only look at my newsfeed if I'm about to about to make a status or something
I voted once a month, it was really even less often than that before, but I just realized that that's a lie. I probably check it a few times a week. My brother posts a bunch of mundane things about his kids every day that I like seeing since they're so cute (3 and 1 years old) and I miss them since i left for uni.