When did American movies get to be so long? It's hard to remember the last time I got out of a theater in less than two hours--and not just for elaborate dramas, stuff like Atonement, but even action flicks. Transformers was two hours and 24 minutes! For a flick based around giant robot cars!
Casablanca was 102 minutes. And it's been years since I watched it, but I don't remember it being a particularly speedy film. Citizen Kane has a running time of 119 minutes. The Maltese Falcon also manages 101 minutes. Comedies, of course, were generally far shorter.
Maybe it coincides with color, since when I look at a few movies from the 70's (Three Days of the Condor, The Amityville Horror, Marathon Man) they seem to have standardized into our now-customary two hours (Soylent Green, however, is still only 92 minutes--OF PEOPLE!).
Now, this is just a feeling I've got. I'd love to see a graph of average movie running times per year, just to see if I'm right. But I suspect that I am, and that films have gotten longer, steadily or perhaps in bursts with each generation. Which causes problems for me, honestly, because my attention span has only shrunk--or perhaps more accurately, has restabilized at 1:30, about the time it takes to watch two episodes of hour-long television in the age of DVD and DVR.
To play devil's advocate, maybe longer running time is a product of the more elaborate film vocabulary in use. Films are no longer just stage dramas performed onscreen. They have a complicated relationship and interaction with the camera's viewpoint, and that relationship requires more time and energy to develop than the static shots of many early filmmakers. This is a reasonable point.
And yet, it seems hard to argue that today's longer movies are better due to their length, or that they're telling more complicated stories. They're telling longer stories, no doubt, with more events and more intricate film technique. But do they need to be longer? Are we better off for having those extra 20-30 minutes of running time? Could anyone honestly say that Casablanca needed an extra half-hour? And if you made it today, how long would it be? Chances are, probably longer than I'm comfortably able to watch.