This week, Google made Android 6.0.1 official, after seeing it on a few Android One devices a few weeks ago it's now beginning to roll out to Nexus devices. The factory images are already available for the Nexus 7 2013, Nexus 5, Nexus 6, Nexus 9, Nexus Player, Nexus 5X and Nexus 6P. However, for those that wish to update and not wipe their phone, they are waiting on the OTA to be available. It's a much smaller file and easier to update. Some OTA's have now surfaced and we've been able to grab the links so that you can now download the update and sideload it to your smartphone and not lose any data (although we'd warn that if you are having issues after updating, to try a factory reset).
For sideloading, you'll want to be sure you are on the correct build before attempting to sideload the update via adb. All you'll need to do to sideload your OTA to your device is plug your device into a computer and make sure adb is up and running. You will need to have USB debugging enabled (for some devices you may need to switch between MTP and PTP). In the command prompt, type "adb devices" without the quotes of course. If it shows the device you're all set. If it shows it as offline, go to your device and give your computer permission. Now type in "adb reboot bootloader", give it a minute or two and it'll reboot into the bootloader. Now you'll want to use the volume buttons to get to recovery and then press power to select. Now you'll see what looks like an error, press volume up and power together to get past that. Now you're going to press volume down until you highlight "Apply update from ADB" then press power to select. Finally you're going to enter the command "adb sideload <filename>.zip" and let your phone do the update. Once it's done it will reboot and you'll be good to go.
Not all of the links are available for all devices at this time. But we'll be sure to update this post once they become available. So you'll want to stay tuned.
Nexus 5 - [MMB29K from MRA58N, 96.3MB]
Nexus 7 (2013) WiFi - [MMB29K from MRA58V, 66.2MB]
Nexus 7 (2013) LTE - [MMB29K from MRA58V, 64.9MB]
Nexus 7 (2013) LTE - [MMB29K from LMY48X, 343MB]
Nexus 6 - [MMB29K from MRA58X, 189MB]
Nexus 6 - [MMB29K from MRA58N, 187MB]
Nexus 9 WiFi - [MMB29K from MRA58N, 169MB]
Nexus 9 LTE - [MMB29K from MRA58N, 168MB]
Nexus Player - [MMB29M from MRA58N, 63.4MB]
Nexus 5X - [MMB29K from MDB08L, 76.5MB]
Nexus 5X - [MMB29K from MDB08M, 76.0MB]
Nexus 6P - [MMB29M from MDB08L, 75.5MB]
Nexus 6P - [MMB29M from MDB08M, 74.4MB]