Handheld systems typically receive a fair amount of puzzle games, and it appears as if the PSP will follow that trend. While many puzzle games don't push the limits of the handheld they're on (which is one of the reasons they get so many) the PSP has the power to handle 3D puzzlers, the first of which is Mercury, from Ignition Entertainment and Awesome Studios.
Mercury looks to be a cross between Marble Madness and Monkeyball, as players will "tilt" the level to manipulate blobs of mercury around the level. While the controls are simple, the game looks like it's going to be pretty addictive. Puzzle elements include splitting the mercury into several colored component parts, each affected by the degree of tilt, in order to open gates and activate switches in the 3D maze-like levels.
While the in-game graphics don't rival that of the proto-type Gran Turismo 4 Mobile screens, they are impressive from a technical standpoint. Much of the game's processing power is devoted to rendering the blob of mercury as realistically as possible, and if you check out the screenshots, you'll see that it does just that. There are also some impressive lighting effects, and while you'd be hard pressed to see it on the small PSP screen, the shiny surface of the mercury actually reflects the surrounding area.
The game is due as a launch title for the PSP, though nobody is quite sure exactly when that will be at this point. In the meantime, enjoy the screenshots, and keep checking back for more information on this promising game.