Sennheiser has partnered with wireless-expert Kleer (who we first featured back in late-2006) to create what has just jumped to the top of my music want-list: the MX W1 wireless headphones, two unattached earbuds and a transmitter dongle/recharging holder that can plug into any audio source for cord-free listening pleasure.
Using a proprietary form of wireless connection, up to four individual earbuds (i.e. two stereo sets) can connect to each dongle; or, assuming the Kleer format is picked up by PMP manufacturers and built into future models, bypass the dongle completely and connect straight through. Audio is apparently CD-quality, extremely low-latency and interference-free, and trips to the mains adaptor are minimised thanks to a built-in battery in the dongle that can fully recharge the earbuds three times before it must be replenished.
The MX W1 set is estimated to reach the US in May 2008, although no price has been indicated.