Single-purpose devices' days are numbered: Manjoo
                                
                                
                                    (Newser) -
                                    After yesterday's announcement that the iPod Nano now has a video camera, Apple's future direction is clear, writes Farhad Manjoo for Slate. Eventually, every iPod will be what Steve Jobs calls a “general-purpose device,” aka a small computer—a music player/phone/camera/web browser/GPS. Sure, Apple still sells dedicated music...