Motorola has been delivering a software experience that closely resembles the one provided by the stock version of Android. The company only includes a few apps to improve such experience bringing additional voice controls or interactive notifications when the phone is locked, but they don't customize the overall aesthetics of the platform. This could lead us to believe that updating the operating system would be easier for this company than those who customize the whole UI, which has been true to some extent, but there are some other companies working faster than ever to deliver such updates. When it comes to Android 6.0 Marshmallow, Motorola is currently testing the software in some models, and those could get updated within weeks.
Some users might have been disappointed when Motorola published the list of devices that would get updated to the latest version of the OS, particularly the owners of the second generation Moto E. This device was released this year, and Motorola had promised to keep it up to date. When the list of devices was announced, Motorola mentioned that it was subject to some changes and now, the company has updated that list adding a few devices. The LTE version of the new Moto E would get updated on some regions, but those don't include the US or China (although Motorola seems to be evaluating bringing it to China). Also new to that list are the shatterproof Moto X Force and the two Verizon phones that were released recently, the Droid Turbo 2 and the Droid Maxx 2.
We can't be too surprised about the last three phones making it to the list as they are considered flagship phones, but given the case with the Moto E, it's reassuring to hear that those phones are getting official support from the company. As a matter of fact, the Moto X Force is already a part of the Marshmallow soak test in Brazil, so the company might test the software in additional regions soon. Let's remember that carriers need to test and approve the updates, so it could take a little longer before we see the Droid phones running Marshmallow.