Airfoil+Bluetooth A2DP receiver?

I'd love to be able to play audio from my iOS device through my mac to the big speakers in my office. Two big advantages over just using iTunes: First, for audiobooks, (I record NPR as .m4b files), you can play at 2X on an iOS device, but iTunes can't do this. Second, you don't have to worry about where you've left off in listening to a bookmarkable audio file. I've found there are problems with syncing the bookmarkable location.

Airplay is obviously closed and limited, but there is another way: A Bluetooth A2DP receiver for the Mac. It could be integrated into AirFoil as a source. It could also control the iOS device playback (start/stop, next/previous). It would require no software on the iOS device. It would require that the mac emulate a bluetooth headset. The only downsides are range and audio quality.

This is possible on a PC:
http://www.a2dp.info/Articles/Using-Desktop-as-A2DP-Receiver.html

I hope you'll consider adding this to Airfoil, or making an add-on.
Thanks,
David