I just can't wait to play this game. It's nice to see some Castlevania characters teaming up, especially when Alucard is around. Yeah!
Oh yes despite their problems providing more DLC,
it's still the most fun, amazing and replayable Castlevania experience ever! Staying true to the Castlevania gameplay people enjoyed for generations while mixing it with even more fun stuff!
IGA should definitely turn this formula into an ongoing series, at the sametime, bringing back the past chapters, so that the selection of chapters, items, characters, etc. carry over, and turn into a even greater series!
Ya this really is like a quality reunion of favorites and innovative teamwork in a Castlevania game. Ya players can solo too, but there's nothing like all of these legendary characters teaming up in a seamless level. It's like the best ideas of Castlevania games combined! ^_^
The only things it trips on is the delayed DLC characters, and well I don't know how complete Chapter 8 and 9 are so far, but they should release those as soon as possible! Chapter 7 really still is a refreshing chapter, but they could still improve in more ways and still make things better!
Ya no Castlevania is as fun and replayable as Harmony of Despair, especially online with friends and strangers alike! Once chapter 8 and 9 are released, and the other characters (Julius, Yoko, Richter, Maria, and maybe Hammer and Simon if they are still in the plans), people will get a better idea how much potential this formula has for new Castlevania games!
Overall, I think Harmony of Despair should start its own growing series! With the advantages of DLC, it has the potential to be even bigger and more better than any Castlevania to date!
The one thing I think they should have done, is include a Fog of War, to enhance exploration a little more,
but that's okay even without something like that.
Just make the enemies and bosses harder and more resistant, add more characters, items, bosses, etc.
and more fun times will come!

Harmony of Despair really deserves to come to PS3 also (and most of them would experience the golden age of Harmony of Despair, which like most games, are always the best when you first start out playing them.) , and
I'm sure when they are ready to make the 1999 Castlevania, they could add all of Harmony of Despair's characters, stages, modes and features as extras! That would be so wonderful!!!!