This is where Akamai comes into the picture. That server would receive all the data from the NYC source, and store it in buffers. That way the person in Tokyo who wanted to access QT streaming content from NYC would not have to access a server halfway across the world, they would instead access a server located in Japan. Since the server in Japan would buffer the content , anyone connecting to it from Japan would only have to contend with getting data from it locally. There still may be bandwidth or connection issues, but the chances of having to deal with those types of problems drastically decreases the closer you get to the geographical source of the content you've requested.
Hops are things like routers that are sitting out there on the internet.
When you request data in Minneapolis that is hosted in NYC, the data may travel to South Carolina, then to Atlanta, then to Chicago, then on to Minneapolis, for example. The more hops you have between you and the source of the data is typically proportional to the geographical distance the data has to travel. The fewer the hops, the less likely there is going to be problems with the data delivery. That is what the Akamai servers do, they localize content servers so that the server is closer geographically to you. This reduces the number of hops the QT 4 content must make before it gets to you, increasing the chances that the quality will be good and that it gets to you in a timely manner, important for streaming content.