This revelation was not made anywhere during the two-hour long announcement of the new iPhones, but they appear on the Tech Specs page for each iPhone model. Interestingly, while their battery capacities are almost certainly different from each other, Apple is stating that the new iPhone models will charge from zero to 50% in 30 minutes. It is of course an approximation, and real world speeds will differ.
Because there is no information on the exact battery capacity, it is unfair to compare the charging speed to that on Android devices, where fast charging has been around for some time now. The fine print on the tech specs page also does not mention the voltage of the charger.
Nevertheless, all three iPhone models supporting fast charge is definitely one of the biggest announcements Apple did not make today. It may not sound as fancy as wireless charging, but it definitely addresses a daily pain point of smartphone users.