Digital television will be broadcast in widescreen mode. Widescreen television has a different aspect ratio (ratio of width to height) than traditional analog.
Widescreen will, in many cases, literally mean you see more of the picture. Most movies are currently made in 16:9 and are converted to 4:3 to allow us to watch them on television or video, so there is a lot of information that you don't see on your television that you would see in the cinema version of the film. Live sporting events will benefit in particular from the extra detail and wider frame.
For some time now television production has been converting to widescreen, both locally and overseas. Widescreen programming is becoming more readily available and will eventually become the global standard.