Currently, inSSIDer does not detect ZigBee as it uses entirely different protocol. However, with a Wi-Spy DBx attached, you will be able to see any RF activity caused by ZigBee as it shares the same frequencies as WiFi. This article talks about this more:
You can pick up a Wi-Spy DBx here for $500.
Furthermore, our Chanalyzer software can overlay ZigBee channels across the amplitude view from the View menu. If this would prove helpful, you can get a standalone copy of Chanalyzer here for $499. Keep in mind that Chanalyzer software requires the Wi-Spy DBx mentioned earlier to function.