This new feature is great for group-discount tickets. (You may find other uses!)
In example that you would like to set a discount of 20% for groups of over 5; first set your price to 20% less and set the minimum per person to 5.
Customers will only be able to take advantaged of the discounted price if they're buying 5 or more tickets.
Find the setting in the "Advanced Ticket Type Options" when creating or updating a ticket type.
(You're still able to set a maximum-per-customer limit, too).