Technically you're not an Apple Watch consumer if you haven't paid for it yet...
It's all about expectations, people. If you preordered a watch expecting it to be delivered on launch day, you have set your expectation. If Apple sends you an order confirmation showing a delivery on launch day, they have confirmed your expectation. If the email shows delivery, say, between 5/13 - 5/27 then they have RESET EXPECTATIONS. If you do not acknowledge this new expectation in your own mind, then only you are at fault.
If you order a bar of soap from Amazon and select next day air shipping, but start complaining 30 minutes after you order because the soap isn't here yet, you need to reset your expectations. Also you are an idiot. The only difference here is that we didn't get to pick our delivery method/window, Apple did.
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They're not behind. So far the deliveries are meeting or exceeding expectations outlined in the order confirmations. If anything, Apple is ahead of schedule with this launch.