The best Bluetooth headphone to buy to be able to do this:

[shlomo80]

Phone 1: WP7
Phone 2: WP8

I want to be able to listen to music from Phone 1. I want to take calls from both.

 

[Cheewii Poon]

I'm not so sure, but isn't the Nokia Luna Bluetooth Headset able to sync with up to two phones at a time?

Nokia Luna with Wireless Charging Bluetooth Headset Overview - Nokia

 

[shlomo80]

It would be pretty amazing if one earset could deliver stereo...

 

[Sammmmmy]

I want to listern to the music while I am calling.