Did somebody blow a whistle and decide that mid-October should be some kind of ad hoc, free-floating film fest? Not really. Current movie-business dynamics are at work, along with some long-held superstitions. Abundant private equity is bankrolling new players in the highbrow movie business, while the seductive charms of the film world have lured businessmen who struck it rich in other businesses (like Sidney Kimmel of Sidney Kimmel Entertainment, and Mark Cuban and Todd Wagner of Magnolia Pictures and assorted other moviemaking entities). David Carr reports.