Yesterday Apple posted Brother Print Driver 1.1. Apple says that the update includes updates for "drivers for printers on your system." Apple also posted an updated for Canon printer users. Canon Print Driver 1.1 provides updates for "drivers for printers on your system."
You can download these updates by opening Software Update (Apple menu > Software Update). Apple also notes that these driver updates will only be available if you have version 1.0 of the drivers installed already, the printer is connected to the computer, and a print queue is created.