After reading hundreds of posts, I decided to post for the first time since waiting for my phone last year.
Firstly, I feel bad for those that ordered literally minutes after 0840-0850 and ended up with a week or two to wait. Been there myself and it sucks! Hopefully people that don't want theirs will cancel their orders and yours will get pushed up, or you can get it before that in store.
Regarding delivery that most people have been talking about - generally, preorders have been shipped to the countries prior to the release date. This means that people in the US will have already started seeing their phones moving through UPS or FedEx, but that's only because it takes so long to get things from one place to another. Even if they are coming from China (like with the 5s release) we still have a day or so before it needs to be despatched...UPS are pretty damn quick! The status is irrelevant, because they only update them once they have had time to go through the logistics, scanning into UPS etc. - either way, I wouldn't worry.
With cases, I decided I wanted a very slim fit case, just to stop scratching. I've read the messages saying things like why would you want to cover the iPhone etc. and I agree...completely. However, I rely on being able to sell my iPhone every year so I can get a new one and if it's not in pristine condition, you're not going to get the same £££ for it. Anyway, I decided to go for the Spigen iPhone 6 Case Air Skin (4.7). I've had the Pinlo Slice and the Desmay Slight before, but neither are available at the moment. Although Spigen are saying pre-order only at the moment, my order, which was only placed yesterday, has already been despatched with RM 1st Class (so should get it before the phone...hopefully).
Anyway, good luck to all getting your iPhones on time. Looking forward to seeing mine!

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Forgot to add, those that wanted a really slim fit case:
iPhone 6
http://www.spigen.co.uk/cell-phone/apple-iphone/iphone-6/iphone-6-case-air-skin-4-7.html
iPhone 6+
http://www.spigen.co.uk/cell-phone/apple-iphone/iphone-6-plus/iphone-6-plus-case-air-skin.html
Also, if anyone wants a screen protector, I highly recommend xtremeguard (though they do send from the US). They are easy to apply, protect well and feel pretty good (I've used them on my 5 and 5s). Also, they are far cheaper than Zagg screen/full body protectors. They've also got a 50% off code running at the moment which shows up when you try to order (if not, its 50off).