Dynamic range. Digital sensors have about the same dynamic range as slide film, or about 5 stops.
My friends had a V1 and one of the things I noticed about it compared to my Canon is the Sony's meter was biased toward preserving the highlights and the Canon's toward preserving the shadows. It looks like Sony is biasing their meters more toward preserving the shadows now.
The first picture the dynamic range is outside of what the sensor can handle and because most of the picture is in shadow(dark) the camera adjusted to make sure the dark was exposed properly and the highlights that fell outside the sensors dynamic range were rendered as white with no detail.
The second picture is mostly in shadow, and the scene falls within the dynamic range of the sensor(no black shadows and no blown out white). The blur comes from the picture being relatively dark and the camera, not knowing you were shooting moving subjects, slowed the shutter speed down enough that it could no longer stop the motion of the people on the street. A faster shutter speed is required to stop the motion, but the lens aperture is probably fully open and the sensor still doesn't have enough light, so it slows the shutter speed resulting in blur. Flash, take the picture in sun, or increase the ISO(sensitivity).
The third picture is taken in a very dark environment, the camera did all it could and found with the lens wide open and the shutter speed pretty slow it still couldn't get enough light so it increased the ISO. The high ISO accounts for the grainy look to the photo. Flash would have helped here.
A book on basic photography will help you understand the relationships between ISO, shutter speed, aperture and dynamic range. I found with my friends Sony, it wasn't the most automatic of automatic cameras. It required some basic photography knowledge to get good photos on a consistent basis. The pictures it took were quite nice though when used properly.