After spending about a month and a half in the beta channel, Chrome is rolling out Google Now notifications to all users. To activate the feature, Google says to sign in with the same Google account used on iOS.
Users can find their cards through the Google Chrome Notifications window. This view is available by clicking the bell icon in the OS X menubar. Cards for events such as weather, sports, directions and reminders will appear just like Now works on mobile platforms.
Some cards that appear on iPhone and iPad through the Google Search app are not currently supported on the desktop browser however and will not appear. More information can be found on the Chrome Help pages.