Can I listen to a single bluetooth mp3 player with 2 bluetooth headphones at the same time?”
As far as I know and have experienced with bluetooth devices, the answer is no. The reason being that the system is set up for one-to-one links for simplicity and it also allows for security in the case of headsets for a cellular phone. As you know if you have worked with bluetooth in the past, when you activate the bluetooth link between the devices, they each have to synchronize. Doing so breaks any link with any other device on the same function. Now, you can have bluetooth set up so that, for example, the cellular phone is attached to both your headset and PDA at the same time but you cannot use two headsets to share the call with someone else nor can two people use PDAs to try to send text messages or emails or whatever else.