I pre-ordered in January 2016, and since then have gotten a few different delivery estimate emails, as they had ideas about things or actual dates came available. In late January of 2017, I sent them an email about my order showing 3/31 delivery, even though the live sales page said it would be delivered 3/3.
I went a few rounds with CS, the first time they said "blah blah, it'll be there when it'll be there" and I politely pressed them for more detail, and a different CS effectively said "it's just a system error, you'll get it on 3/3", which sounded great.
I got the same email as many of you last night, and my order status shows that it's been delivered, but with no delivery date. I pulled up my old email exchange from a month ago and asked for any more detail they could shed light on. We'll see if someone knows anything.
In the meantime I placed an order to pick up at the local Best Buy. The first couple days of the month are crazy busy at work, but I'm sure I'll be able to sneak away at some point and grab it. And then I'm not waiting until 8 pm for the UPS guy to make it to our house.