It honestly depends on the size of the game, and the skills of the developers. Some games have been made by a single person (usually the small online flash games) where large games like Lost Odyssey or Final Fantasy would have a full studio of dozens of people.
It depends on your interests and what your good at. For example, Many people enjoy video game testing or development.
There isn't a official Warriors video game but many people can program short games.
lots.
lots
500,000
3-11 years
Many video game design software packages exist. Some of the more popular ones include Unity3d, 3d Game Studio, Game Maker, and Westwood Game Development Systems.
Many people do, all over the world.
none, the games suck
they really happy and exciting.
yes the first video game was Tennis for Two but many people think it is pong
Many times major video game corporations will have "testers" or people qualified in video game testing that are paid to come to a facility and just play video games for a living. Other people can go to events where games are shown for the first time and pay to play the game on the company owned systems and games.