The zombie is here to stay. It will always be one of the biggies, for a few reasons.
For one thing, it doesn't require much in the way of elaborate costuming, so it's within reach of a lot of budgets. It doesn't take a lot of makeup know-how to pull one off, and the clothing is likely your own old garments.
Two, they're gross - be they fresh and besmeared with gore, corrupted with radiation burns or infectious disease, or crumbling with age from eons in a crypt, the gross-out factor makes them popular.
Three, they're fun. They have the hand-eye coordination of a mop bucket and the reasoning skills of a hammer. They eat people, they're nearly indestructable and they represent the complete collapse of the norm, which has always been one of the attractive elements of Halloween. They're societal chaos mixed with equal doses of horror and comedy.
They may be more abundant this year, but zombie walks are springing up in every major city, more movies and novels are featuring them and even zombie art and jewelry are becoming common.
My point is, if you believe that zombies are more popular this year, I'd say the evidence agrees with you... just as it did last year, and the year before that, and the year before that.
