Well I DM, but we don't play at my place. We usually spend the last 5 minutes of each session figuring out when we'll play next (that varies sometimes, depending on a set of circumstances). I -still- always call the guy who's house we play at every "game" day, to confirm, since he's the one people call if they can't make it, after all. That isn't strictly necessary, as he's very, very good at calling people if stuff came up to cancel the game, but I had a previous group (in which I played) with which I suffered through too many horror stories, which put me off ever "assuming" again that stuff would go on as planned.