First day with the Siri watch face...
This morning I was shown 'cards' for my two morning appointments, the days weather and sunset, a breathe reminder, a general reminder, alarms I had set and the days News headlines. It's midday now and I've since had a Now Playing card popping in whenever I've had music on, I have a timer card right now showing remaining time left and another weather card just popped in alerting me that it will begin raining in two hours.
Super cool so far, way better than standard complications or switching between multiple faces at different times of the day. With a little more customisation and tweaking and access for third party apps this will be really good.
They've removed Maps as a data source which is unfortunate.
There are currently toggles for cards from:
Alarms, Breathe, Calendar, News, Now Playing, Photos, Reminders, Stopwatch, Timer, Wallet, Weather and Workout.