More companies are providing Development Platforms for ZigBee. The ZigBee Alliance validates and certifies these hardware platforms and calls them "ZigBee-compliant Platforms" (ZCP).

Going forward, I see ZigBee being a great way to implement active RFID tags. ZigBee defines 3 types of devices:

• ZC - Zigbee Coordinator: initiates network formation, the RFID interrogator (reader).
  
• ZR - Zigbee Router: participates in multi-hop routing, could be used to extend RFID read range.
  
• ZED - Zigbee End Device: low cost/low power, the active RFID tag.

****

Look here for list of ZigBee Chips and Modules.