you're missing a lot if you're into web design. of course, content is king and google fucked up big times by not having a proper fallback. but that parallax scrolling is the best I've seen so far https://www.google.com/ideas/products/digital-attack-map/
The parallax scrolling on that page is mediocre IMO.
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.
http://www.firewatchgame.com/