Maybe one of the biggest Apple “secrets” will be that the iWatch will use the new continuity and handoff features in iOS 8? That would mean that we can answer phone calls on the iWatch and send and reply to messages with the new audio/video messages feature for example.
And it would be the perfect way to “sell in” the new 5.5-inch iPhone 6 phablet to the loyal iPhone users too. I mean, they can say something like “thanks to the iWatch you don't always need to have your phone available, it can still lay in your bag while using the features you need on your iWatch instead, and pick up your phone when you really need it”. Of course said a lot better than that but you get my point.
The iWatch could be marketed as the perfect companion to the 5.5-inch iPhone 6 phablet. That could be why the rumors says that the iWatch won't be released until October. The normal 4.7-inch iPhone 6 in September, and the 5.5-inch together with the iWatch in October. Brilliant.