I love my Apple Watch, not only because of what it does, but what it doesn't do. It doesn't have facilities to surf the internet, to watch films, to FaceTime people, because it's just not a great experience.
I can see why a camera may be useful for apps like Snapchat, but seriously, who wants to take a FaceTime call on their watch? Hold your arm up to face-level for 30 seconds and see how it feels, and now imagine talking to someone for minutes like that. Madness.
Hope it offers improvements in other areas as well, as if the main selling point is a camera I for one won't be upgrading.