geh, in my opinion, from what I've gathered lately Bluetooth is now in a fair number of different items and planned for more and it would be a pity for those with those items to lose support. Bluetooth is sort of mid UWB while UWB is full blown UWB and the thinking is that to merge the standards for Bluetooth and UWB so that one with Bluetooth can access something provided in UWB and vice versa makes a lot of sense. ZigBee is not UWB but links nodes and items together in a mesh network. I'm not exactly sure where it fits in this mix - as a control for items, perhaps, which items receive their info via Bluetooth or UWB. The range for Bluetooth is meters, while for UWB is tens of meters, I think. Then Wi-FI which is hundreds of meters.