It's unnoticeable when not using smooth scrolling (my personal default). Not a huge problem for a design feature to be unnoticeable though.
When smooth-scrolling using the middle mouse button on Chrome/Linux, it doesn't update dynamically as it scrolls; the background snaps into position when scrolling stops. In Firefox/Linux, it does update dynamically with middle mouse smooth scrolling, but jerkily. It's noticeably bad in both browsers.
or maybe their intent was to bore me off their site because I'm not a journalist. In that case they did well!
I used to work for one of these companies, and we built quite a few highish-profile sites for Google and YouTube. The quality of work done by this company varied wildly between excellent and utterly dismal. Project management interactions with the Google side were haphazard at best and chaotic and disruptive at worst. Requirements would constantly change, and the designs would be all over the place. I don't think one time we thought about accessibility. A number of the projects were death marches, and I worked on at least one huge failure, which fell over on a live TV show with millions of viewers.
TL;DR - just because it's on google.com doesn't mean it was designed or built by Google.