Brian Moody of Edmunds.com wrote an excellent article in May 2006 that will answer your question. Here is an excerpt.
" The advantage of Bluetooth-enabled devices is that Bluetooth is a standard operating "system" for lack of a better word. Various devices from diverse manufacturers can communicate wirelessly. Foley notes, "In many cases, involved companies may be competitors or have nothing in common except for Bluetooth. For example, Bluetooth makes it possible to use your favorite Microsoft keyboard with an Apple Power Book." Also, with a Bluetooth-enabled camera (or camera/phone) you can wirelessly transfer photos to any Bluetooth printer and get instant prints. You can also compare and synchronize calendars in your PDA and transfer files, music or photos from camera to computer or computer to computer or from phone to phone. With Bluetooth-enabled phones you can wirelessly transfer contact information, meeting requests and e-mail messages to other paired devices.
From an automotive perspective, Bluetooth offers the ability to utilize your personal cell phone through an in-car system. Cars like the Chrysler 300C, Jeep Grand Cherokee, Saab 9-3, Toyota Prius and others offer Bluetooth as a factory-installed feature. Other automakers that currently offer Bluetooth capabilities include Acura, Audi, BMW, Bentley, Cadillac, Dodge, Ferrari, Infiniti, Jaguar, Land Rover, Lexus Maybach, Mitsubishi, and Nissan. Expect many more models to offer Bluetooth by the 2006 model year. What makes Bluetooth so appealing (in addition to ease of use) is its relatively low cost. For example, Chrysler's system is called UConnect; the option costs about $290 and consists of a Bluetooth receiver (mounted out of sight), a microphone and a small control pad mounted to the dash.
Aftermarket kits are also available if you're not in the market for a new car. A company called Parrot makes several adapter kits as does Motorola and others. The kits are very affordable with prices starting well below $200.
Even if you do opt for an aftermarket system, Bluetooth offers all the safety and convenience of a factory-installed car phone combined with the freedom of a handheld cell phone. The user must have a Bluetooth-enabled cell phone in order to take advantage of the in-car feature, but those phones are becoming more and more common and are not significantly more expensive than phones without Bluetooth (some Bluetooth phones are even less expensive than a phone without the feature). Cell phone makers such as Motorola, Nokia, Samsung and Sony-Ericsson currently sell phones with Bluetooth capabilities.
With a Bluetooth phone, you can make and receive calls from your car using your existing cell phone number. You use minutes in the normal way and the charges show up on your regular cell phone bill. But perhaps the best feature is that to make and receive calls on your Bluetooth phone, you don't need a docking station or hard-wired connections. OnStar has a similar feature, but it requires that you have an OnStar-equipped car (usually a General Motors product) and you must use Verizon as your cell phone carrier. Even then, your car will have a separate phone number and you will have to forward your cell phone calls to your car phone. With Bluetooth, if your phone is on and somewhere in the car, you will be able to make and receive phone calls. No call forwarding is necessary as the phone "sees" your car like any other external accessory — similar to a wireless headset. If the car's interface or your phone allows the use of voice commands, you can make and receive phone calls while in the car without having to touch any buttons.
The application gets even more interesting for motorcycle owners, as the availability of a Bluetooth-enabled helmet makes it possible to talk on the phone while piloting a bike — not that we're endorsing that kind of thing. In cooperation with Motorola, Italian helmet maker Momo has developed a Bluetooth helmet that not only looks cool, but has an integrated speaker and microphone. This is not unlike preexisting technology that allows bikers in close proximity to talk to each other via two-way radio technology, but clearly the ability to make and receive phone calls pushes the technology forward by leaps and bounds. The BMW System V helmet uses similar technology but is a full-face helmet which makes talking on the phone a more realistic endeavor.
While the potential for Bluetooth technology seems almost limitless, its introduction into the automobile could prove to be more than just convenient. Both the federal and local governments have been increasingly scrutinizing the wisdom of letting motorists talk on the phone while driving. Bluetooth could be a technology that offers a safe compromise between those who want to exercise their inalienable right to yak on the phone and those whose job it is to protect us from those who yak on the phone while piloting a two-ton chunk of steel and glass.
Ease of use combined with increasing availability leads us to believe that Bluetooth will soon become as common as big hair at a Bon Jovi concert. If you're shopping for a new phone, PDA or camera, find one with Bluetooth capability. In the end it will make your life that much easier."
Go here to read the full text of this article: http://www.edmunds.com/advice/specialreports/articles/103685/article.html