First impressions? The adaptive triggers are the most impressive things to happen to controllers since dual analogue sticks. It's absolutely seamless, and it just goes from "oh that seems like a cool feature" to "oh no this is HUGE" over the course of one level in astro's Playroom. Devs NEED to use this tech, it's game changing.
Oh god I can't wait to have this thing in my hands, and I've got to wait until the 19th too :(