Too many people have confirmed getting it OTA (plus the fact that phones recognize it as a signed Moto update) for it to be fake. At the same time, I believe Verizon when they say they aren't rolling out the official update.
I'd guess it's either a slip on someone's part, or else it's a test with a limited number of participants (in which case either those people are violating an NDA, or else once again it was a slip on someones part).
Anyways, this would appear to be "official" in the sense that it's been sent from Moto and VZW to at least a few people, but they'd probably prefer you not to install it yourself until they can vet it.
If the OTA goes out in the next week or two then it will probably be this version. If it isn't then they presumably found some problems they wanted to work on first.