Promised long ago, Wren has finally shipped out V5BT ($399), the Bluetooth version of its earlier V5AP AirPlay speaker. Looking at the unit, you likely won't be able to find any differences, as the body is the same. Internal components have changed, though, with this edition simply using the less expensive, more universal wireless audio streaming standard -- yet with no corresponding change to the price. Bamboo and rosewood finishes are available,…