Game Ratings

Game Ratings are a new feature introduced to ROBLOX games on June 18th, 2013. Players who have visited the game and verified their account can "thumbs up" or "thumb down" a game. This was made to nudge the Games page closer to ROBLOX's vision with "a Games page that's loaded with fantastic games to play and worlds to explore." The rating system is known to be similar to YouTube's own rating system.

Blog Post
http://blog.roblox.com/2013/06/thumbs-up-to-game-ratings/