Unfortunately, I have to hope this doesn't see widespread adoption. If this becomes the standard it will just add to already existing social pressure to get an iPhone in the US.
> anyone can RSVP, regardless of whether they have an Apple Account or Apple device.
Non-Apple users cant contribute to the playlist. No mention on the impact to the shared photo album. If its just a normal shared Photos.app album, non-apple users are locked out there, too.