Google Now places a notification in my tray for weather and commute times - can I make it do the same for reminders?
Strangely, after "snoozing" one of the reminders via the Google Now page (essentially forcing it notify me in 10 minutes), the notifications for all other reminders started working again too.

I've tested both location based reminders and time based reminders. Seems like I inadvertantly switched something "on" by forcing one of my existing reminders to snooze for 10 minutes.