For those of you who were worried about Google's current Android devices not receiving Android 7.1 Nougat, don't be; Google has confirmed that the Pixel phones' current software version will be arriving on Nexus devices and the Pixel C before the end of the year. However, these devices won't be receiving some Pixel-exclusive (Pixelsclusive?) features.
Google has informed us that before the end of the calendar quarter (aka before 2017), Nexus devices and the Pixel C will receive a developer preview for Android 7.1 Nougat. It's unclear which Nexus devices will receive it, but the 6P and 5X definitely will, and the 6 and 9 might.
Also unclear is exactly which features from the Pixel phones will carry over to Nexuses and the Pixel C. We do know some things - for the time being, the Pixel Launcher and filled nav buttons will not come to older devices. It's almost certain that the Support tab (24/7 customer service) will not carry over, since that's a major Pixel selling point. However, it has been confirmed that the Night Light (blue light filter) will come with the dev preview.
Obviously, Google wants to keep some Pixel features exclusive so that people actually buy the phone, but it's good to hear that some stuff will trickle down to older hardware.