RE new movie theaters (an area datadyne007 will confirm I am well-versed in), the trend with new movie theaters is fewer seats and a more relaxed atmosphere. Assembly Row was one of the first locally to have La-Z-Boy-style seats in all screens, which seat half as many people as a traditionally-sized screen. Regal Fenway has recently undergone a similar conversion. Their smallest screens use to sit 100 people... now they seat closer to 48 patrons each. As someone that's studied crowd reactions and behavior at the cineplex, I can attest that people seem willing to shell out more money for a night at the theater when they have the comfier seats, alcoholic beverages, and more premium foods (which is where these theaters make their money in the first place).
ArcLight at the Hub on Causeway and Showcase at Seaport Square will definitely be in this vein, and definitely fulfill demand for that kind of experience downtown. Regal Fenway is set to lose a couple of their largest screens when the Wegmans redevelopment of Landmark Center begins, so it is not surprising at all if they are looking to partner with Tremont Crossing for another 8 screens. And, finally, I think I recall reading something about a theater going in at South Bay Center's redevelopment--right?
It might seem like a glut of new theaters, but the reality is that--like our hotel market--Boston theaters average some of the highest ticket sales per screen in the country. Developers and planners are finally beginning to catch up with market realities that people are ready for new movie theaters in the area. And they're being much smarter about where they're building them... I think every single new theater is within 1/4 mile of a "T" stop, which is remarkable!