Here's how it works: Filmmakers are invited to submit 2-15 minute videos to the Amazon Studios site; the process works just like script submission. Creators can submit either privately or publicly.
After that there is a 45-day option and evaluation period, during which Amazon decides whether they'll option your project or not. If they decide to buy it (and its associated rights) they'll pay $200,000 for a movie script, and $55,000 if it's a script for an episodic series.
For more info on their venture and for instructions on how to submit click HERE.