I'm generally not one for Stereo Bluetooth.  I use my phone as a music
player all the time, but prefer wired headphones to wireless since they
generally sound a lot) better and also don't require recharging. 
Granted, that limits me to phones that have standard size headphone
jacks (since I'm a giant snob and use fancy earphones and not the
garbage that comes with musicphones) but it's worth it.

Sony
Ericsson sent me a Stereo Bluetooth accessory that's got me singing a
different tune, though ... so to speak.  The MBS-100 "Bluetooth Ball"is a black sphere of speakers, amp and Bluetooth receiver that fits in
one hand, runs off of a rechargable battery, and actually sounds pretty
good.  The Ball pairs with any Stereo Bluetooth music source via the
A2DP profile, and also accepts wired connections via a 3.5mm line-in
jack.  And in a nifty little trick, the line-in jack doubles as a
line-out jack, meaning that you can use the Ball as a Bluetooth
receiver wired up to a stereo system or higher quality set of powered
speakers.

And in all honesty the sound quality of this little ball far, far exceeded my expectations.  On the one hand those expectations were pretty low thanks to the legions of crappy powered speakers that have flooded the market ever since Apple's iPod caught on several years ago.  On the other hand, the MBS-100 actually sounds quite good given its small size and the limitations of Bluetooth audio.

Am I going to replace my home stereo with the MBS-100?  Yeah, right.  But could I see a home for the Bluetooth Ball, say, out in the backyard during Summertime parties and hooked up to the bedroom stereo the rest of the time for use as a Bluetooth receiver?  Absolutely.  The combination of above average portable sound (with a rechargeable battery built-in) and Bluetooth receiver makes for a pretty nifty little accessory.  Nice job, SE.