I'm a little wary of how this changes what a class is, but only a little. Why can't I be a "vampire sorcerer" or a "vampire warlord"?
Ideally the Vampire class will come with Hybrid rules and a Multiclass feat.
For things like vampirism, or lycanthropy, or... well, other conditions, classes seem like a pretty logical solution to me, so long as Hybrid and Multiclass options are there.
(By the by, I'd heard somewhere that Heroes of the Feywild will include the first dual-role class, but that the class will only be capable of filling one role at a given time. My suspicion is that that book is where the previously announced werewolf class that was to be in the Ravenloft RPG too, has gone.)
Anyway, one interesting trend that's becoming rather visible is how many concepts are being re-treaded in different ways.
Will I be able to play a Vryloka Dhampyr Vampire?
Should I be Shadar-Kai, a Shade, or use the Haunting Shade feat, to get my shady-shade darkgrim on? Some combination there of?
Don't get me wrong, I like having the options. I just think it's kindof cute how far one idea can stretch.
Similar to how I could drink Coca-Cola, but I could also have a Pepsi, or RC cola, or tuKola (Which is a cuban brand, and actually my preference, generally. [Though one I seldom get to have...]).
I could also use a glass, or a bottle, or a mug... straw or strawless...
Options.
I am looking forward to Heroes of Shadow - because, honestly, I could actually use more distinctly shadowy options. It will be comforting to have a decent amount of Shadowfell (Or Shadowdark, or Shadow...) material in case my players decide to head there. (Which is looking very possible in my current game. The Human Ranger has already taken Haunting Shade.

)