IMHO, one of the best Bluetooth headsets you can buy (after getting the swing of putting it on and off) is the Aliph Jawbone. Today the announced a new model that has several improvements that look like they actually listened to what consumer wanted changed. There should be one at my house and a review will be coming shortly.
The new Jawbone is available today in AT&T retail stores or via AT&T and Aliph's sites for US$129.99. It is 50% smaller than the current model and has a cooler design. Thay really tried to focus on making it look like a fashionable accessory so you don't look like a dork wearing it around all day. AIt comes in gold, silver, and black. I think the new leather earstrap looks more comfortable and easy to attach so I look forward to trying it myself.
They use their NoiseAssassin technology (developed by DARPA and not to be confused with the Darma initiative) with Voice Activity Sensor and Digital Signal Processing to give you the experience where background noise is removed while your voice is clear.
The new Jawbone weighs 10 grams compared to the previous model at 14 grams. Battery life is stated to provide you with over 4 hours of talk time and over 8 days of standby, which both exceed the capacity of most of my phones.