Not every Bluetooth product supports every profile, and some of these - like A2DP which is used to send stereo sound to a headset -- are still being worked on and are particularly problematic.

Well, that is just the start of how hairy Bluetooth is. Some Bluetooth USB dongles - not to mention the built-in Bluetooth support in desktops and laptops -- don't support all the various profiles, so you could get into a situation where you have a Bluetooth keyboard that doesn't talk to your PC, but a headset that does, with the same dongle. Or, you have a Bluetooth keyboard that installs software that gets in the way of a Bluetooth headset, because the two devices support different profiles. This isn't yet a consumer-friendly place to be, let alone an enterprise IT friendly place.

The next issue is when you pair the same Bluetooth part with multiple devices, such as cell phones and computers, or you want to do more than have a remote headset. Then you have to rely on the PC makers' different implementations of Bluetooth protocol support. On my year-old Dell laptop, its built-in Bluetooth adapter was almost worthless and could barely connect with anything. I found after looking at more than a dozen products that many of them worked fine as long as I used the Bluetooth USB dongle that came with the product.

I had some better luck with a USB dongle from Toshiba on Windows, and a D-Link USB adapter on my Mac, but it was still touch and go. (Most Macs come with their own BlueTooth support, but I didn't have it on mine.)

If I installed several different dongles on a PC, which you might want to do when testing a bunch of different products, the computer would get confused, and I had to resort to re-imaging the entire drive to clear things up. That's because the Windows support for Bluetooth makes changes to the Registry, so getting rid of it will require some careful surgery. This isn't yet for the general user, where the words "re-image your drive" strike fear into their hearts. (Here's an of one form of re-imaging, called cloning.) My recommendation is to find a USB dongle that will support the widest collection of devices and stick with it as your corporate standard. Of course, then someone will come along with a nifty new device and that will send you back to the drawing board.