David Schuster, Senior Director of Software Product Management at Motorola Mobility, says that they're still "soak testing" the upgrade, "monitor it for a few days and, with good results, proceed to full deployment." However, the folks over at Droid-life are confirming that the update is already available to regular users - thus, we assume that everyone is about to get it. This is a two-part update, and you can manually check if it's available for your Droid Turbo 2 by going to Settings -> System update -> Check for system update.
Android Marshmallow is bringing a lot of new features to the Droid Turbo 2, including a new app permissions model, Doze (a feature that increases battery stand-by time), Now on Tap (providing Google Now contextual results), enhanced settings and controls, and so on. You can find out more details about the update at Motorola and Verizon (see the source links below).
In case you want to buy a Droid Turbo 2, the handset is currently offered by Verizon starting at $24 per month for 2 years, or for $624 outright. For a closer look at the smartphone, make sure to check out our Droid Turbo 2 review.