http://accessories.us.dell.com/sna/products/Networking_Communication/productdetail.aspx?c=us&l=en&s=dhs&cs=19&sku=M960G&mfgpid=198272&chassisid=8273
Just got this new 370 bluetooth card in and fixed all the issues I was having w/bluetooth audio...
Following shows the diff between the old & new 370:
Notice the later version HCI Firmware that shipped w/this new Mini-card on the bottom...
Dell Wireless 370 Bluetooth Minicard Application 6.2.0.6600 driver from here:  http://ftp.us.dell.com/network/R205174.EXE
Updated:  Bluetooth driver linked above will auto-flash up to latest HCI firmware pictured on the bottom!:)

Lastly, I also downloaded and installed the Windows Vista Feature Pack for Wireless:  http://ftp.us.dell.com/network/MICROSOFT_WINDOWS-VISTA-SP1-_A01_R204794.EXE

This article describes the Windows Vista Feature Pack for Wireless. This software update includes the following components or features that improve wireless support in Windows Vista: • Bluetooth version 2.1 support
• Unified Pairing user interface
• Windows Connect Now updates
Some of these features may work with existing hardware. However, you must have new hardware to take advantage of the new functionality.
This update is compatible with all versions of Windows Vista. It can be installed only on a computer that is running Windows Vista Service Pack 1 (SP1).
This fix for bluetooth was never made avail for download by Microsoft and only given to OEM's but I managed to find both x64 & x86 versions here:  http://itsvista.com/2008/05/kb942567/
After installing this hotfix, you get a new show bluetooth devices window in Vista!
Everything now sounds great over my Motorola bluetooth headset...  No more pops or dropouts with this new 370 card w/improved firmware and the thing was cheap at only $10!:D