As I reported in the thread on the introduction of Apple Music, it appears that certain functionality has been lost since Audio Books were moved from the music app to IBooks. Or, at the very least, the functionality has been so well hidden that I can't find it any more.
For example, I cannot find any way to synchronise an audio book to my Apple Watch.
Also, last night, I set ITunes running on my laptop so that I could share the library over wifi from another room on my IPhone. Needless to say, I couldn't find any way to get IBooks to share the audio books on my ITunes library in the way I used to be able to from the Music app.
So, if anyone knows how to address these two problems I'd be grateful. However, if anyone else can confirm the loss of these features, I'll raise it with Apple.