The current track and current playlist properties return a -1731 “unknown object type” error when run against a currently playing Apple Music track. That’s going to be a problem for scripts and apps that use those properties to identify a playing track. I couldn’t say if this is intentional or a bug.
The iTunes XML reports the main Library name as “####!####”. This is not necessarily AppleScript related, but several of my scripts may refer to this “Master” playlist by obtaining its name from the XML.
More as it develops.