With the iPad comes new iTunes. MacRumors hears that 9.1 will have a minor overhaul, organized around books, and smarter, more customizable Genius mixes.
The Audiobooks section will become simply Books, which'll show all of the book stuff you've got in iTunes, sorted by compatible device (iPad vs. iPhone). And of course the device sync screen will change accordingly, so you can manage your book content, along with minor tweaks like moving the "check for updates" button.
In terms of new powers, Genius mixes will be more customizable, and you'll be able to use them as sources for iTunes DJ. Also, other devices are supposedly picking up a perk from the iPod shuffle, which is auto-converting tracks to 128kbps AAC when you sync, saving space on the device but leaving your bigger source files in iTunes.