The addition of the Apple Watch to the customer's pile of devices (or the "Internet of the customer" to be trendy) is not a radical change in itself. However, it signifies the need for dramatic change in the way we market to customers.
As technology has evolved and new marketing channels have been created, marketing teams have grown into siloed groups that focus on functional areas such as branding, in-store, direct mail, online, and now mobile.
Now, of course, the Watch will most likely not become the responsibility of a separate team. I imagine in most (if not all) cases, Apple Watches and other connected devices will fall under the responsibility of the mobile team.
So what's the big change?
What the watch does represent is the blurring of lines between what have traditionally been seen as different "channels" by marketers. The addition of a connected watch potentially brings mobile content a step closer to customers when they're actively looking in-store and when they're out in the street.
For example, if potential customers are looking at a garment on a rack, they are unlikely to have their phone in their hand at the same time, but they will be wearing their Apple Watch. At this point, the Apple Watch becomes more powerful because of its proximity to the customer.
You now have an opportunity to deliver customers relevant, contextually appropriate messaging with the highest chance of it being viewed at that very point in time.