The Predacons are here in this season 3 trailer entitled: Beast Hunters for Transformers: Prime.
IGN was given the exclusive trailer and here it is in all it's entirety:
Sharp eyed fans will recognize most of the footage used in the trailer was from NYCC this past year. Also of note, Shockwave is being voiced by of Beast Wars fame, David Sobolov (he voiced Maximal Depth Charge on the show). Though he's not the first of the Beast Wars allum to appear on the show. David Kaye aka Megatron himself voiced the Insecticon Hardshell in two episodes of Season 2.
Transformers: Prime- Beast Hunters will arrive in the spring of this year. Unlike previous seasons which had twenty-six episodes, the season will only be sixteen.