Finally came last Thursday (early March 2017), after ordering at the beginning of January. I had exactly one listening experience prior to purchasing; in the Apple Store, for 15 seconds. It was enough time for me to listen to a bit of my favourite song, so I could instantly tell how they compared to my 3.5 mm EarPods. I loved them.
A few nitpick-y things, such as Siri being deadass slow (okay, maybe because of my iPhone 6 which iOS 10 seems to hate), and not being able to use apps such as Sleep Cycle whilst listening to music (apparently the speakers in the AirPods interfere with the microphone operation in an unusual way).
But, this is all software fixes. I'd imagine Apple will overhaul the visual and sonic interface of Siri, or at least for AirPods (so it doesn't stop all audio/video if you just want the volume cranked up a bit).