In keeping with its tradition of drip-fed information, Blizzard sent out a tweet about the fate of the Horizon Lunar Base. For those Overwatch lore buffs out there, they'll know that the Horizon Lunar Base is the location in which Winston, the game's gorilla, PhD., grew up. The details about the moon installation have always been scarce, but it looks like we're now getting some information.
The tweet linked to a blog that goes over some of the supposed information that has been coming out of the long-thought inactive lunar base. What's most interesting of note is the last image, which shows a list of specimens, all gorillas, that are accounted for, except for two: Winston and Hammond. We know what Winston has been up to, but Hammond is something of a mystery. The only real info we have is that he's missing, and that he's likely a smaller test subject. The text reads, "I don't know why we ever thought it was a good idea to have smaller test subjects," in a message concerning Hammond. It's possible he's not a gorilla at all, but possibly a monkey.
Though there is no solid confirmation of an upcoming event, the chances of one are highly likely. Blizzard has released info on upcoming heroes before, including Ana and Sombra, in this manner. The final image also has a map of a facility that, while purely speculation, looks just symmetrical enough to be a new map.
Purely speculation, however. No doubt there will be a lot of theorizing and clue hunting in the weeks to come.