They have a new Sonic the Hedgehog game: Sonic: Lost World!!!!! This is the first game since Sonic Adventure 2 to NOT have the Boost System. In fact, Sonic has NEW tricks to show off.
Based on the info I collected, Sonic AND Dr. Eggman team up to fight the Deadly Six. Why? Because the Deadly Six used to work for the Doctor, but they betrayed him.
This game is AMAZING!!!!!!!!!! It is similar to Super Mario Galaxy, but still Sonic Style with the "playing as a blue hedgehog that can run 756 miles per hour". They reason why I say it is like Super Mario Galaxy is because of the spherical terrain.
I know very little of the plot, but this is what is known.
Sonic is chasing Eggman to the Lost Hex, where Dr. Eggman is using the Deadly Six to his advantage. Unfortunately, the Deadly Six betray the Doctor and forces Sonic and Eggman to team up.
One of Sonic's new tricks involves him doing acrobatics while leaving behind after-images of himself. He also has a Spin Dash, but that is actually not a new move. In fact, Sonic could use it in the VERY first Sonic the Hedgehog game.
But this game is not out yet, and is only on the Wii U and 3DS.
Here is the box art. NOTE: THIS IMAGE IS FROM WIKIPEDIA THE FREE ENCYCLOPEDIA.
The dudes above Sonic are the Deadly Six.