The first season of these events will begin on February 23rd and continue through April 7th. It will be made up of 109 events that take place solely on the weekends, and it will feature different start times so that players across the globe won't be at a significant disadvantage based on location.
There are several ways to win prizes through these races. Players accumulate reward points that contribute to both season and lifetime prize tiers, and they can win additional goodies if they place in the top ranks for multiple events and the season as a whole.
[Thanks to Josh for the tip!]