One of the new features in Microsoft's Achievements system on Xbox One includes the ability to color-code pop-ups in local multiplayer games to help clarify which user received which Achievement.
An example of the new system can be seen at the 11:15 mark of this video first streamed on the official Microsoft Twitch.tv account. In the current Xbox 360 Achievements system, the player that unlocks an Achievement is highlighted by a light that appears around the Xbox 360 logo corresponding to their controller.
Xbox One, however, will let players choose a specific color that will fill the Achievement pop-ups and notify the group who received it.
A full run-down of the new system can be found right here, and introduces both changes to Achivements and the introduction of user Challenges. Xbox One is slated to arrive next month in North America.