If you’re into using apps that aren’t actually ready for prime-time (a beta or developer build of Chrome, for instance), then you’ve been experiencing all of Google Now’s glory, with the added notifications. However, for the rest of us that aren’t so gutsy, Google Now is arriving for Chrome’s stable version — the most common.
From related info, voice search, reminders for events, flights, TV etc., with location-based cards like commute times and typical Google Now features one may have already been accustomed to on the Google iOS app or current Android phones.
FYI: Don’t worry if you don’t see it yet; updates from Mountain View usually take a few days to roll out.
Via: Chrome Support