Been following the thread for a few days. I'll finally add my anecdotal experience:
Early last week I opened up a new t-mobile account in anticipation of pre-ordering online. I figured having an account open ahead of time would allow me to setup an account early and have less hoops to jump through come pre-order day. Explained this to the rep in-store and he set me up with two temporary numbers and waived the sim fee for me.
The friday fiasco came, I took a short "nap" at 3am PST and woke back up at 4am to see that preorders were live. After 15-20 minutes of unscuccessful online ordering, I called customer service and waited ~15 minutes on hold. The rep was super friendly and got my order for a 64GB iPhone 6 (grey) and a 64GB iPhone 6 Silver. She very confidently told me I would get mine on the 19th (I took it with a grain of salt). Signed the EIP I was sent and got a confirmation copy at 4:45am PST on the dot.
Yesterday my order history changed to "BackOrder 09/17/2014 at 03:17:16 AM" and then from Backordered to preordered. No changes since then when checking via my.t-mobile.com
My credit card was charged the evening of the 16th for the full amount (charge is still pending). Since then I seem to be on the tail end of all the developments I've read here. Lots of people got the "it's coming friday!" email during the day yesterday and I got mine at 7:15pm yesterday. Robolady finally changed her tune to "processing" not long after people here got that. No shipping information via ups.
Finally, tonight I decided to chat with customer service online for the heck of it:
RonnieM: Hi!
RonnieM: I understand that you want to know the status of your order. No worries, I'm here to help.
RonnieM: Let me go ahead and pull up your account and check on this.
Me: thanks
<looooong pause>
RonnieM: Thank you for waiting. I just want to ask, have you already received an email or a text message that says something like "Free T-Mobile Msg: Great news! You should receive your iPhone 6 on Friday." Thank you for your iPhone 6 pre-order. Great news! You should receive your device on Friday.
Me: yes, i received an email last night stating i would receive it friday
RonnieM: Great! That's good to hear! Let me just confirm that hear.
<even longer pause>
RonnieM: Thank you for waiting. I'm happy to inform you that your phone will be delivered tomorrow. Unfortunately customers who participated in the iPhone pre-order are beginning to receive notifications that their orders are being shipped. However, the notifications do not provide order tracking numbers. As of this moment we don't have the tracking numbers yet, however I want to assure you that your order is a priority for us.
So, that's where I'm at right now. Aside from the pre-orders not going live on time or working via the website (ok, that's a big one), everything else has been a smooth pleasant experience for me. Even if I don't actually get it tomorrow, I always find the week leading up to the release entertaining/fun. Good luck everyone!