Transformers 2 director Michael Bay has informed MTV the runtime of the sequel. “It’s four minutes longer than the last one,” explained Bay, saying that the runtime was locked. The 143 minute time of the first movie + 4 = 147 minutes long movie. “I don’t ever talk (to executives) about run times,” [Bay] grinned. “Studios always ask, ‘What’s the run time?’ And I’m like ‘If you enjoy the movie, do you care?’”
The reason runtime matter to studios is it reflects the number of showings per screening. So a 90 minutes movie might have 7 showings a day to five for a 150 long movie. Over 3000 or so screens that can be a lot of money the studios think they may not get. However, I think its nonsense. A sell out does more for a movie's word of mouth (an excited, full audience raises any viewing) then a half empty theatre will any day of the week. Besides, if someone wants to see the movie, less show times during the day isn't going to stop them, especially with all the screens the movie will likely appear on (my guess, 3.5k). Thanks to Mcat for the link.