Not such a big surprise afterall
A bunch of hoopla is spreading in Transformerland due to the typical spooky Japanese methods of teasing new figures. We see a black silhouette of an upcoming toy with no size indication or explanation.
If you look closely, the profile very closely resembles that of the newly revealed MP12 Sideswipe prototype, minus the giant shoulder cannon. My guess is this is a remolded Decepticon version of MP12 as Breakdown. Simple as that.
EDIT: I was wrong