IPhone :: Syncing Audiobooks To 4?

I just don't understand how Apple handles audiobooks. I have a variety of books which have been either ripped from CDs or downloaded from Audible. The ripped books are in my library by following the steps below:

1. Insert disk; join tracks; hit import

2. When the whole book is on the hard drive, select all files; get info; change media type to audiobook

3. Create smart playlist with two criteria - 1) album name; 2) plays=0

When I plug in my phone, under the book tab, the playlist/book will appear in either "Audiobooks" or "Include Audiobooks from Playlists." Sometimes this will be in one; sometimes the other; sometimes both. Can't figure out a pattern.

When I synch my phone, my books often, but not always, show up under the Audiobook icon. Sometimes they show up under "Playlist" and then under "books."

how to make this more dependable? why itunes separates the two locations for audiobooks?

Info:
MacBookAL, Mac OS X (10.7)