To give you an overview of your retention state, you get all key metrics when you open the Retention Analysis tab:
revenue per customer
orders per customer
time between orders
By clicking on Details under each one, trend graphs are ready at a glance.
Where's the old graph that showed how customers are distributed by order count?
It is now a convenient color-coded line still on the Overview page, under the metrics.
It visualizes the ratio between new and returning customers in a quickly-to-grasp way.
If you click on Details for either group, you'll get an accumulated trend graph again.
For returning customers, you'll also see something close to the old bar representation of customers by the number of orders, but this time it's a line. When you hover over the different-toned segments, you'll see the share of customers with the specific number of orders: