Did they ever make a huge announcement at Combo Breaker the last time? I can't remember.
I do know that we have a habit of thinking that the FGC is a big thing in the world, and forgetting that this is a multimillion-seller AAA game.
Remember the, "They're gonna reveal the next MK at EVO" people? Strategically that doesn't make sense. You get maybe 150-200K people watching the biggest main events at EVO. Not sure how many people were tuning in to MK on Saturday night, but making an announcement there isn't a huge splash in the bigger gaming world.
Combo breaker might be different though, since it's something smaller w/ the DLC. If they've done it before, my bad.
NRS seems to usually either go huge with the big announcements (E3) or just go direct to major press and social media (IGN/Twitter/Gamepot etc.)