These are the gimmicks that Apple pre-programs into Siri. One of many ways, like the random answers for Siri, the phone is designed to amuse, entertain and convince the unsuspecting, that it's a magical device.
It's the one huge difference between the pretentious Siri and the more authentic, straightforward Google Now. Free of gimmicks and jokes Google's intent is to provide additional service, not gimmicks. It's faster, smarter and completely devoid of gimmicks. Very refreshing.