Maybe Google is nervous that Apple's lawyers are watching, but for whatever reason the Chromebook Pixel's pinch to zoom feature on the touch screen doesn't work with most websites out of the box. The good news is that you can enable this feature yourself. First type “chrome://flags” in the address bar, then scroll down and select “enable pinch scale”. Restart your Pixel and voila! This option should be enabled out of the box. Unfortunately, pinch to zoom doesn't work on most websites with the otherwise awesome glass touchpad.