"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Apple Watch Vulnerable to Theft With No Activation Lock
As pointed out by iDownloadBlog in a detailed post on the security of the Apple Watch, there is nothing that stops a lost or stolen Apple Watch from being wiped and paired with a new iPhone. The Apple Watch has a passcode option that requires a sequence of numbers to be entered every time it's removed from a wrist, but the passcode protects only data.
The passcode is also easily bypassed with a reset. Pressing down on the side button of the Apple Watch brings up the power down options and a force press on this screen brings up an option to Erase All content and Settings. Erasing the Apple Watch in this manner erases the passcode and allows the Apple Watch to be paired with a new device, with no hint of the original owner's information available.
Because there's no Activation Lock and because the Apple Watch is reliant on the iPhone, there's also no Find My iPhone option to locate a lost or stolen Apple Watch. Due to this lack of security, it's possible the Apple Watch will become a major target for thieves.
It's an expensive device (especially the higher-end Edition versions), it's compact, it's highly desirable, it has a high resale value like all of Apple's products, and it's easily visible on a wrist rather than hidden away in a bag or pocket like an iPhone. In short, it's an easy target for muggers.
iPhone theft in major cities like San Francisco and New York became such an issue that government officials called for Apple and other cell phone manufacturers to implement a "kill switch" that would disable stolen devices, leading to the eventual release of Activation Lock alongside iOS 7.
Activation Lock had a positive impact on smartphone thievery, dropping iPhone theft by 25 percent in New York, 40 percent in San Francisco, and 50 percent in London as of early 2015. If Apple Watch theft causes crime rates to spike like iPhone theft, it's possible lawmakers will once again step in to call upon Apple to improve the security of the wrist worn device.
As iDownloadBlog notes, Apple could potentially introduce stricter security measures in a future version of Watch OS. A simple solution would check the last known Apple ID of a paired device, refusing a new connection without a password or other authentication. Given the number of sensors in the Apple Watch, it's also not unimaginable that a future biometric solution could also be implemented for additional security.