(the link in the second tweet was a post saying the game had been canned)
The game in question is the flash move horror game we only saw in a few montages prior to the Move launch. Like a certain wizard game (which is still in development), it vanished without a trace.
Now this game was actually never formally announced. However, SCEA trademarked a bunch of names, including "Until Dawn" - sounds like a horror game, no? Well, according to PSM3, "Until Dawn" and the untitled Move horror game are one in the same.
PSM3 did list this as a rumor, so I can't say if Until Dawn is the Move horror title, but President of Sony Computer Entertainment Worldwide Studios said this horror game still exists. So big Move games like this, and Sorcery are things to hopefully keep the peripheral relevant.