In short, the technology allows for backward decoding so that if an error occurs, it can play a redundant frame or two while it finds the glitch, then resume at a synch marker fairly seamlessly. Not only are movies coming soon to an ISP near you, the demonstration showed, but they'll be arriving on wireless devices. Separating the media into component parts lets data flow more smoothly down the Internet pipe. For instance, a video clip could consist of a background image, an actor, some dialogue and some music. More asynchronous parts like the background and music score could be delivered earlier and would sit at the user end, appearing as static on the screen or waiting for a cue to play.
Tiger is separate from the green.
You could zoom in on him and view his face in close-up. If you focus on the green, it'd be blurry. It's features like these that make MPEG-4 very attractive to advertisers. But when the standard rises from pirated films and becomes more mainstream, don't necessarily count on a free ride. The bottom line is that MPEG-4 offers a standard that both user and producer will be able to take advantage of and enjoy.