The former you'll find in any document you've embedded an animated GIF in, and the latter you'll find where you normally find shortcuts and widgets you want to place on your home screen.
Also pretty cool is the new training video you see when you first run the app. It's very "new Google" and worth wiping data on Drive just to see it.
The update is slowly rolling out to all devices, so make sure you check the Play Store regularly.
[via Android Central]