"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Apple Preparing In-Store Pickup Option for Apple Watch
To date, Apple Watch orders have been taken exclusively online and shipped via UPS or other couriers to residential or business addresses, but soon customers will gain the option of ordering online and visiting a local Apple retail location for in-store pickup. Customers will be required to present a valid government-issued photo ID upon pickup, and must match the name on the reservation to pick up the product.
Apple originally planned to offer in-store pickup of the Apple Watch as early as April 24, although later decided to take orders exclusively online and ship to home, possibly due to limited supply resulting from faulty Taptic Engines. When in-store pickup for the Apple Watch becomes available, customers will be able to select a nearby Apple Store location of their choice to pick up the product.