This Vampire trend is nothing new. It's been going on for a long time. They will always be popular in one way or another, because you have the more monstrous ones as well as the suave and sophisticated ones to appeal to different kinds of people. The emo mask they wear now (which does suck) is just the newest way to sell them to ignorant children. Once a new trend takes hold that the vampiric mold can be shoved into, they will become that. Check out the cock-rockish vamps from Lost Boys in the 80s to see what I mean.
Zombies are kind of an anomaly, because a good zombie film doesn't treat them as a character. They are treated as a more natural force. Zombie movies aren't so much about the zombies, as they are how the humans react to them. Some of the better zombie movies are more about taking a look at the current state of human society through a zombie holocaust. The original Dawn of the Dead is a great example of this.
That said, every zombie/vampire movie made since the 1990s started has been total garbage (other than satiric ones like Shaun of the Dead). If you want good horror, it ends with the 80s.