Does the success of “Chicago” and “Moulin Rouge” mean movie musicals are making a comeback? “It wouldn’t be the strangest trend to ever sweep through pop culture, but it wasn’t that long ago when talking about a revival of movie musicals would have been akin to speculating on the horse-and-buggy craze that was just around the corner. In fact, today’s 18-34 crowd has been watching musicals since they were kids, in the form of all the Disney movies that got popped into the VCR whenever mom and dad needed a break.”