An earlier pos in this thread contained an image with chat support who said that Apple's procedure of not charging until shipment is a favourable method. This means that they must be shipping now and with rumours that they're already in the country, I have no doubt we will see them on Friday.
I agree I don't see why they would charge us now if they aren't planning on shipping them anytime soon. When I initially placed my my order I was charged £0.00 by Apple, that's how it showed up on my statement. It dropped off sometime last week. I've now been charged the full £299 for my watch.