I literally check my order status on samsung.com hourly hahaLol! I know! The only thing I can remember worse than this I experienced was the Nexus 6P. I actually looked back at my emails a couple days ago and it was 22 days from the time I pre-ordered until the time the device was shipped.
So far Samsung/T-Mobile are over half way to beating that. I was hoping it would ship today or tomorrow so I have it by Saturday. But that was wishful thinking. Looks like next week will be the earliest since that's the ship date most people for T-Mobile have.