I've just had a quick hands on with some of the upcoming noise cancelling Bluetooth headsets from Sennheiser. And I must own them.
I had chance to check out two different models: the PXC 310 BT and the MM 450 Travel, and even though they were pre production, the sound quality was superb. They look fantastic and were also extremely comfortable.
In regards to concerns over the battery, apparently you'll get about 22 hours just as a noise cancelling headset, using an audio cable instead of Bluetooth (which is also an important feature for when you're on a plane). If you turn on Bluetooth and have the volume all the way up, you can expect about 8 hours.
The MM 450 also includes a microphone, with a dedicated button to receive and end calls when paired with your phone.
At the moment there are still no prices set, although we should see them on shelves mid to late next month.