Psyonix has had massive success with Rocket League and for the first update of 2016 they are closing out the first competitive season and introducing a new item type. After the update, which is set to drop sometime in February, uncommon item drops will be active and an “Item Qualities” system implemented. They are as follows:
Common (Grey): Stock items. Pretty much everything you have earned previously
Uncommon (Light Blue): Earned playing online matches
Premium (Green): Things you have paid for
Limited (Orange): Earned in season or during promotional events (like Halloween)
A new item type, Uncommon, is earned after online-only matches and include new Toppers and Antennas. Unlike other items, your chances of earning an uncommon item increases the more you play the game. Once it has been obtained the timer will reset your chances so it can build up again to repeat the process. You can view an example of an uncommon item in the image at the bottom of this post.
Sometime in February when the patch drops the first competitive season for Rocket League will also end. When this happens players will be given Limited Edition Crowns in Bronze, Silver, Gold, and Platinum colors. They are all equipped as Toppers for your car, and are based on the highest division rank you achieved by the time season one ends. So if you failed to make Bronze in most divisions but are great in 1v1 you will get whatever rank you reached in that one.