Tablets are huge gaming devices. It is a natural progression for any tablet maker (even one focused so heavily on eBooks) to find a future in app and online games. Amazon is following the pack--ensuring that it's Fire is stocked up with games.
In order to fuel the Fire, Amazon has created GameCircle, "a new set of services designed to make it easier for you to create more engaging gaming experiences and grow your business on Kindle Fire."
The goal of the new program is to make it easier to implement common gaming functionality and tools, such as leaderboards, badges, trophies and achievements. Most importantly, Amazon leverages it's huge cloud infrastructure to allow games to sync in-game progress to the cloud. This will allow users to put down their device every now and then to have a snack or get some exercise without losing their progress in-game.
Amazon hopes to attract more developers and help them grow their business using Kindle Fire as a gaming platform. Simply said, the goal of GameCircle is to make developers happy and make it easy to build games.