In case you're having trouble telling them apart, Silent Hill Townfall is the new Silent Hill game being developed by Stories Untold studio No Code and published by Annapurna Interactive. Not the Silent Hill 2 remake or the prequel set in Japan called Silent Hill F. When Townfall was announced during Konami's Silent Hill transmission, creative director Jon McKellan said, "It's a real honor for us to bring a new title to this series that both respects the source material, but also does something a little bit different with it."
He concluded by saying, "So obviously the teaser trailer is just the beginning, we can't show you any more, [...] it might be worth watching that trailer again, and see what you might have missed." The internet took that as a challenge, and has already found some secrets buried inside it.
Most significantly, Redditor u/MilkManEX downloaded the trailer's audio as an m4a file, had a look at its spectrograph in Audacity, and found text that reads: "WHATEVER HEART THIS TOWN HAD HAS NOW STOPPED".
Pausing the flickering images that play across the pocket television also revealed text that says, "THY FLESH IS WEAK", as well as three dots, three dashes, and three dots: Morse code for S.O.S. That's not the only code fans have discovered. When developer No Code tweeted an image of a house, and publisher Annapurna Interactive tweeted a similar image, it was obvious they weren't identical pictures. Which is why @yApth0 subtracted one from the other and found more Morse code, which reads, "I DON'T KNOW HOW TO LEAVE".
Spooky. Other things rounded up by the Silent Hill subreddit may be more of a stretch, especially when they seem to be referencing the earlier games in the series. For instance, 33 seconds into the trailer when parts of a map are displayed, it sounds kind of like someone saying "Is that really Alessa?" in reference to the character from the first game. But it's real fuzzy audio, and probably wishful thinking.
As is the theory that the figure seen 45 seconds in is Valtiel, first seen in Silent Hill 3. The idea that the other creature seen sideways around 49 seconds in could be a Lying Figure from Silent Hill 2 is a little more convincing, given that it shares the awkward, shuffling posture and bodybag-plastic sheen.
Given McKellan's statement that Townfall "respects the source material, but also does something a little bit different with it" we probably shouldn't expect too many direct callbacks to the fan-favorite original Silent Hill games. The teaser's narrator, interviewing someone about why they're in Silent Hill, at first accepts the answer they're here to be punished—which is why most of the main characters in Silent Hill 2 are drawn to a destination unlikely to score high on Tripadvisor—but then says there's probably more to it than that. Maybe that's true of Townfall itself? Given how overused the iconography of Silent Hill 2 in particular became in later games, that sounds like a good thing to me.
If someone could piece together all the map fragments and figure out where they're from though, that would be ace.