Originally Posted by Andrew H.
I don't think that any iPod plays protected wma files, which AFAIK is still what most OD books use.
Correct, iPods don't; but, there's a licensing agreement that allows these files to be converted for use on iDevices.
Every now and then, I'll download WMA library audiobooks to my iPod touch; though the conversion process is rather lengthy. Most of the time I just download them to my Clip Zip.