Until now, the Nest Thermostat integration was focused on turning heat or AC on/off when a tag that monitors temperature reports "too cold", "too hot" or "back to normal".

We also receive current temperature and humidity updates from the thermostat and save it for historical graphs (up to 10 days per Nest policy). The temperature update allows triggering "too cold", "too hot" or "back to normal" events and KumoApp event handlers assigned to "temperatureChange" or "temperatureCross". This means if you have another WiFi thermostat including ones from Honeywell, you can choose your Nest Thermostat as if it is a temperature sensor tag in the "Set At" option to make it turn on/off another thermostat.

Nest Thermostats contain sophisticated algorithms to use sensor (a PIR?) and scheduling to determine if the house is occupied or not (i.e. "home" or "away"). Nest encourages developers to use this information in an integration. 

Starting today, the Nest thermostat "tag" will generate "Detected Movement" (i.e. transition from "away" to "home") and "Timed Out" (i.e. transition from "home" to "away") events just like a PIR KumoSensor. You will also be able to assign KumoApp event handlers to "detected" and "timedOut" of the Nest Thermostat to perform actions like arming or disarming motion sensor tags, as well as use corresponding IFTTT WirelessTag channel triggers. 

From the Web/Android interface you can click the ">" button to open a PIR sensor-like notification option screen for your Nest where you can choose emails, twitter account, push notification sounds for these events. 

Also, now if you have configured the "Set At" for your Nest such that HVAC is triggered by a wireless tag, when your Nest transitions to "away", temperature monitoring of the tag will be automatically disabled (so it will not try to turn on HVAC when nest is in "away" mode), and when Nest transitions to "home" the temperature monitoring at the tag will be re-enabled. This is actually a feature a lot of people wanted and long overdue. 

 We are pleased to announce that all Wireless Tags PRO you buy on or after May 27 will include these exclusive updates:

• Choosing too hot/too cold temperature monitoring thresholds at 0.02°C step:
  The Wireless Tag PRO uses the same digital temperature and humidity sensor IC as Wireless Tag (with 13-bit temperature/humidity) which has a resolution of 0.02°C (13-bit). However, until now thresholds were stored in 8-bit numbers, so you were only able to set thresholds at ~0.6°C step (the accuracy of the threshold is unchanged with this update). This update is especially powerful when used in conjunction with Nest/Honeywell WiFi thermostats, because you are now able to regulate temperature much more precisely using too hot/too cold events from sensor tags.
• Programmable sampling-rate for temperature monitoring:
  This allows trading off battery consumption with the response time of the tag to temperature events. Because the tag only transmits readings when the temperature crosses a threshold, not when every time it samples (checks if temperature is too high or too low), setting a fast sampling-rate like every 30 seconds has much less impact on battery life than setting a 30 second auto-update interval.
  
• Hardware delayed notification:
  When you are using the tag to monitor temperature inside a fridge or freezer, your purpose is to get notified when the compressor breaks down or exhibit chronic problems. You probably don't want to get notified when temperature increases temporarily because the fridge/freezer door is opened for loading/unloading. "Delayed notification" allows the too-hot or too-cold event to be transmitted only when the sensor reads too-hot or too-cold for a programmable number of times, in a row. A similar feature is available currently in a KumoApp script but it was based on auto-update/logging data points, and drained battery more quickly because a relatively short auto-update interval must be used for it to work. 

New temperature options in Web/Android and iOS (2.4.11+) available with the new Wireless Tag PRO