Unfortunately, we know little else about the game at this point.
Will it be a 3D runner like the Bronze Award-winning Sonic Dash? Or maybe a 2D endless runner that hearkens back to classic Sonic titles?
We don't know. However, photos of the announcement do suggest that Sonic Team is working on it rather than Hardlight - the studio behind Sonic Dash and Sonic Jump Fever.

We do know that Sonic Runners will be released in Japan first before heading anywhere else in the world. It should arrive in early 2015 over there.
We'll let you know any more details about Sonic Runners once we get hold of them.