I kind of have to agree with Sumac's last statement there, LoS
is Castlevania because Konami said so. If we were in charge of the IP (intellectual property) we could delegate what is and isn't a Castlevania title.
Hell if it we wanted to go wild we could retcon Bloodlines and PoR and call them Bram Stoker's Dracula: Revenge of Quincy and Bram Stoker's Dracula: Generations Defiant or something. Does it really make sense? Not really, they sure do play like Castlevania games and their settings are similar. But the do lack playable Belmonts from the get go and their plot seems to play off of Stoker's original novel more than established Castlevania plots of the time.
Oh! And we could make that Van Helsing movie an official CV movie if we were in control of the IP since it has a Castle, Dracula and hordes of baddies to defeat! We could say in some manual off to the side that the Helsing clan are like 3rd cousins to the Belmont and that's good enough, right? I mean, they're even referenced in the game, so there
is precedence to tag a CV title to the beginning of it!
Damn it all I say, Konami has the final say on what constitutes as a CV title, much like how Paramount dictates what is a Star Trek title and Lucas for a Star Wars title. Do we necessarily like it? No, but we do accept it since it's their IP. I just don't
get why LoS is constantly regarded as
not a Castlevania title by some members of the community. Is it because we're racists and think only the Japanese master race could do it any justice (thanks for the compliments but we aren't that great)? Was it because it was linear like a traditional CV title? Was it because it had too much emphasis on combos like LoI? Was it because there were outdoor areas like in CVIII? Had a different soundtrack that introduced unique tracks while remixing familiar tracks like SotN (bad example I know, SotN OST > LoS OST erryday!)? Is it because the Combat Cross uses a chain whip like Richter's in RoB? Weird monsters? Questionable plot twist like in AoS where the main protag is really...?
I mean, I am absolutely dumbfounded by this. I mean, I enjoyed LoS, I feel it's a CV title, but I also don't think it's the best CV title. How hard is it to admit that it's a CV title? If Konami slapped Castlevania over a MGS like game where you have to sneak into an old castle as a single spec op operative and shoot silver/holy rounds into monsters and stuff, I'd buy it and accept it. It would be a little weird, but it is Konami's IP and I just don't see where we get the audacity to decry something as
not Castlevania when it's clearly stated otherwise.
/soapbox
TLDR; Why some think LoS is not a CV game? Konami own CV and say what CV is and isn't, QED.
Back on topic: seriously why do some people think a Japanese made CV would be inherently superior to a western developed CV? I could make a CV game, use my Japanese passport street cred and I'm sure it would be worse than if I challenged oh...let's say Visceral to make a CV title to compare against.
/soapboxingagain
Seriously, why this dicotomy of games being Western/Japanese (Korea wants love too!)? Why can't they just be
games that were good or bad like when we were kids playing our NES/SNES/Genesis or what have you? Did we care if Sonic was Japanese and Lemmings was British? I didn't! Did I care Street Fighter was Japanese and Mortal Kombat was American? Nope! I liked them both for what they offered. They were just
good games. With this age of globalization I don't see why we make these barriers and sections of this/that based on origin. Yeah the flavors are a little different but it's all consumed the same way and we either enjoy them or don't.
Maybe I'm looking too far into it, but whenever I see/hear that any Japanese dev would do CV better than a Western dev all I hear is this:
http://www.nbc.com/saturday-night-live/video/j-pop-talk-show/1362560 
Sorry for the long winded post, just something that's been bugging me since my return to the dungeon. *prepares for -1 onslaught*
When's it due out?
According to Amazon March 1st, 2013.