The site is indeed registered for Frictional, and the domain information also points to TheDarkSwarm.com -- a possible hint at the new game's title -- which leads to an unplayable browser game and a timer that continuously ticks upward every second. The source code on both sites mention first-person perspective, horror, action adventure and other qualities we've come to associate with Frictional. The Dark Swarm site was registered way back in 2007, and was updated in September of 2011, so it might be unconnected.
Frictional's Thomas Grip told us last year that the studio was working on "an Amnesia-related project." At the time, he said that the project wouldn't focus solely on creating fear, but will hopefully "evoke other, less primitive, emotions as well." If that means it will feature even a few moments without teeth-clenching, panic-stricken fear, we're all for it.