I'm assuming based on everything I've seen here that I shouldn't expect my order to arrive on Friday. I opened a new account w/ T-Mobile over the website and completed my order at 8:01am PDT, and got my confirmation e-mail shortly after (not as easy as I make it sound, but it did work pretty well once I actually got through to the checkout).
Anyway, I believe I saw a message during the process that said it would ship/arrive by 9/19, but I've since called the customer service number provided on my confirmation, and it says my order is backordered.
I'm switching from Verizon back to T-Mobile after jumping around carriers the past few years, and I'm looking forward to being back on their network. The phones are essentially "free", since my girlfriend and I are out of contract on Verizon but obviously still paying the subsidized price. I really appreciate what John Legere has been doing to try and shake things up. Hopefully the phones arrive sooner than later, but even if they don't come this Friday I assume they'll be here next week.