I'd say as hazy as the future of the series is right now, it's in a slightly better place than Mega Man is. Even though most are against the direction Castlevania has gone over the years, at least Konami is trying to keep the series relevant. They could have easily throw the series into the vault along with Suikoden, Goemon, Gradius, Axley, Sunset Heroes, Rocket Knight, Snatcher, Policenauts, Boktai and so many others but Castlevania games were still being made alongside with their other key franchises like Metal Gear, Pro Evo Soccer and Silent Hill. So I feel confident that a new Castlevania is already in the works, be it a 2D game or otherwise. Just when we'll hear about it I do not know, maybe after The Phantom Pain comes out and some dude will leak info of the game out of nowhere.
Meanwhile, Capcom looks like their just about done with Mega Man, or hell just about every other of their series not named Resident Evil, Street Fighter or Monster Hunter because they dont sell 2 million copies.