To my knowledge there's only been one trailer for Dark Shadows to show up, and I'm assuming that first one is the "comedy cut" trailer. I'd be surprised if it wasn't edited to show the majority of the slapstick type scenes the movie holds, with the intent of catching a wide range of people to see it in theater. My guess is the full feature length film will have it's "scary" bits, intense bits, the gamut.
Abraham Lincoln Vampire Hunter also looks very cool. Based on the book by Seth Grahame-Smith (who wrote Pride and Prejudice and Zombies as well).
As far as vampire movies you don't have to own a time machine to see, a lot of the stand-out choices have already been mentioned, so I'll try to dig a little deeper:
From Dusk Til Dawn - Rodriguez/Tarantino style saloon vampires with lots of gunfights, quickfire dialogue, and Cheech Marin. Lots of fun, and vampire burlesque strippers.
Fright Night (2011) - The original has been mentioned, but the remake from last year was a oft-looked over gem in my opinion. Skip the first Act, really. Kid has school problems, why doesn't the girl like me, mom doesn't understand, blah blah. But when it kicks in, the film really was enjoyable. Stay tuned for David Tennant (of Dr. Who fame) as a not-so-fraudulent Las Vegas vampire slayer.
Vampire in Brooklyn - Are you ready for a jerry curl wearing Dracula? Probably not.
Blood And Donuts - For a, well, how do I say this and not completely turn you off?... It's a little hipstery, if you take my meaning. But it's honestly got a touching story and the quirkiness is endearing as well. Not exactly a horror film, per se.
Have fun!