When we switched our movie bookings to a week at a time (in addition to making several improvements and changes to the theater), we've noticed a major increase in movie attendance. Back when we took over the theater from the previous owners, if we had 30 people for one night, we considered that to be a good night. Now we get a lot more people coming to our theater on a regular basis. Now I won't say that the booking change is 100% responsible for the increase in attendance (as we've worked on our concession products, updated the projection and sound equipment, and improved customer service) but I certainly think it has certainly helped. And like I said, our customers know to call our hotline to find out what's playing. Even when we get a big movie at our theater (like Wild Hogs), we'll get our posters, signs, emails, and hotline message out on the Monday before the weekend and by the weekend, we're turning people away!
If I'm not mistaken, it seems like most of the big theaters won't release their showtimes until either the Friday of a new week, or a couple of days before Friday (especially if they are advertising in a newspaper). So there would seem to be enough people to either call or visit that theater's website or just show up in person to find out what's playing. And also, with the window between a film's theatrical release and DVD release getting shorter and shorter, you don't want to book a film too far out when it's very close to its DVD release.