Night mode is an automatic setting that takes advantage of the new wide-angle camera that's in the iPhone 11 and 11 Pro models. It's equipped with a larger sensor that is able to let in more light, allowing for brighter photos when the light is low.
PowerBook and iBook Confirmation? [Updated]
According to the site, "Apple will introduce revised 12-inch PowerBooks (two models), two revised 15-inch PowerBooks, one new model of the 12" iBook, two new models of the 14" iBook, and a single high-end 17" PowerBook configuration".
Limited availability is expected next week.
Update: ThinkSecret also provides confirmation of a Monday release of iBooks and PowerBooks.