Right now is very much Android 6.0 (Marshmallow) time. Google released the final version of the latest version of the Android operating system at their annual Nexus event a couple of weeks back. This was also followed by Google announcing the roll out of OTAs to Nexus devices, the factory images going live and also the code being uploaded to AOSP. This last point making it possible for everyone to jump on the code and do as they wish with Marshmallow.
By now, manufactures will already be knee-deep in converting and porting Marshmallow over to their particular flavor of Android. As a result, the last week or so has already seen numerous reports from manufacturers making it known that they are working on delivering Marshmallow to their respective devices and even some suggestions of what sort of time-frame should be expected. In fact, some companies, like Motorola for instance, released a list of devices which would be seeing the update once it is ready. However, in the case of Motorola's list, the list received some unwanted attention due to a couple of notable exclusions from the list. One of which was the Moto X (2nd Gen) for the U.S. on AT&T and T-Mobile. This inevitably lead to some questioning whether the carrier variants of the Moto X (2014) in the U.S. would receive the update at all. A question which to the dismay of many, seemed to be answered when a Motorola forum manager confirmed that they won't be seeing the update.
Well, whether they will or will not be receiving the update might not of been as simple as we first thought. Wi-Fi certifications for both devices have now been spotted and interestingly, both listings refer to the operating system as "Android, version:6". Now the obvious assumption is that this is Android 6.0 (Marshmallow) and that both devices will receive the update. However, the date of both certification filings is September 30th. Which was before the list of Motorola confirmed devices was released. So it is currently unclear if the list didn't include them because there is an issue with updating them or whether it is still something the company is working on.