It's definitely not getting an Android 6.0 update, but the original Moto X is still getting Android 5.1.1. As is customary (i.e. required), Motorola has posted the kernel source for the update. You can grab it on GitHub if you're the developer sort.
Kernel source doesn't do the average user any good directly. However, this open source code lets developers track down bugs in apps, create better custom ROMs, and build tweaked kernels. For a device that's about to be left in the dust, this is important stuff.
Interested parties can grab the ZIP file below, which weighs in at 135MB. Everyone else, sit tight and wait for the magic to happen.