I've got to say I am surprised that people are so opposed to this. I am actually more than a little excited. I would be very excited if they hadn't been claiming to be getting started for about a decade now. But given the people involved I think if it does get made it will be pretty fantastic.
A. We've got a script by Warren Ellis. Now while it certainly does seem to deviate pretty heavily, it was clearly a jumping off point. Almost anyone familiar with Ellis' work would attest that it is almost all pretty great.
B. Ardi Shankar, whose fashion sense I legitimately don't get, is actually a pretty stellar producer. His short films are always simultaneously very true to their source material, and at the same time grittier and more geared towards adults. Punisher: Dirty Laundry, and the film Dredd are just two great examples of this.
C. Frederator Studios are pretty great animators, and the idea that they would do Castlevania in the same style as Adventure Time, or even close is just laughable. We've seen concept work of what this is supposed to look like. You guys forget about this?
Now well yes, I am picking the best one, the other concept art we've seen for this is all pretty good, and far from anything resembling adventure time. The Alucard one is pretty rough, but we've seen worse.
Given that this thing has been going on for 12 years now, I'm willing to bet the script has evolved. It only ever told about how Trevor, Sypha, and Alucard got together, a point I am certain this series would go beyond. And given Shanker's track record on adapting properties I am willing to assume it has either stayed as true to the games as it was, or gotten even closer. I am psyched, and I hope it does come out eventually. A kickass Netflix series could rejuvenate the franchise. Save it from gambling machine purgatory.