Demos include The Darkness 2, Scarygirl, UFC Undisputed 3, and just in time for the 12 for 12 sale to be over, PixelJunk SideScroller. You can also download the Gotham City Impostors beta.
We also must mention what we think is the best PlayStation Plus deal ever: a Capcom "Super Pack" of Super Street Fighter II Turbo HD Remix, 1942 Joint Strike, Age of Booty, Wolf of the Battlefield: Commando 3, Super Puzzle Fighter II Turbo HD Remix, Flock!, Rocketmen, and the "It Came from Uranus" expansion for $12.50. Total. See all the new content on the PS Blog.