So, while on Facebook, the Sonic Adventure 3 page shared this link.
Apparently this year's new Sonic game. It's in Japanese but there is a translation in that link.
Or for easier reading here.
Translation: Sonic the Hedgehog 2013 • Propel is a working title • been started at the beginning of the 360, PS3, Wii U version will start later • have been developed by Sonic Team Sonic Colors segment • No indication of being developed for the next Microsoft and Sony machines • Successful re-release of Sonic CD digital art direction inspired by the realistic, more of Propel • Model Sonic's slightly shorter repetition of classical and modern now, between the body and a rounded spine stiffer, and thin limbs, modify its contents, shorter • The slow movement for a more accurate distribution of more fine tuning, use the mechanics generation • modified hedgehog engine often running on better lighting and motion blur • Plot of minimum • The deployment Eggman each with the design and features five special metal Sonics, unique • We will restart Death Egg • significantly reduced dialogue, more action-based cut scenes • Eggman says more than the other characters. • focused on the exploration stage • act as a power-up option similar to trail you can "assist" characters hidden in the stage, open the secret path • Tails as Sonic 4, function ability assisting character fly • The progress at the level of the shadow branch Hedgehog style, it is not a multi-level access route by Hoop, goal • 3-level structure method. Your goal ring which has reached, we determine whether to initiate a position in the following method. Reached to the progress of the cut scenes and story of changing 3-Determination Act, which is the goal ring next step is changing the boss stage occurred slightly Challenge acts hidden • 3 per stage • Stage "Evergreen Escapade" first • require multiple theater take a different route to collect the Chaos Emeralds of options, all of them After the emerald has been collected, • Supersonic at all stages • All Emerald final battle secret has been collected, • You can disable difficulty modes Easy, Medium, Hard, bubble tips and warnings • 3DS version is being developed by Dimps • 3DS version, we use a completely new graphics engine • Shift to a segment of which is controlled 3D 2D, a touch pad on the main 3DS version • different storyline 3DS version • Alternate assist character Tails But in both versions of the edition 3DS,
This is only a rumor and not yet confirmed right now.