Have you ever been in a situation that warranted the need for instant access to your phone's camera? Then you fumbled around, unlocking things and swiping all over, only to miss the moment. Shame, really. If only there were a way to grab your phone and say "take a picture!" and make it happen.
Google apparently knows your pain, so you know what it did? Added "take a picture" to the voice actions in Search. For good measure, "take a video" (or "record a video," as shown in the above image) is also an option. So instead of swiping to the camera from the lockscreen* or unlocking and tapping an icon, you can now launch Now and tell it to take a picture or video... at which point it will open the camera in the applicable mode.
Because that's clearly faster than doing it any other way.
* – Applicable handsets only.