would be nice to be logged in forever?

Not sure if its just me, but when I leave the site and come back a few min later, I'm already logged out. Same thing occurs when I leave it idle for 5-10 min? Why don't these act like regular old forums like vBulletin or something and let us stay logged in. I use facebook to connect. I don't know if it matters if I actually sign up for the site.