I listen to audiobooks on my iPhone and am missing the high-speed playback I can get on almost every other device. I'm surprised that folks haven't risen up in revolt over the limited options in settings/ipod/Audiobook Speed.
I am willing to pay $$ for an enhancement that gets me more than the 25% speed increase. Ideally 50/100/200/400 as in iPlay for WM (
http://iplay.40th.com/) or WMP, or ...
If you are willing to work on a solution I am willing to contribute. Just PM me. Thanks! Audiobook listeners of the world will forever sing your praises.