In the U.S. dogs seem preferred among the younger generation (and possibly in general, I don't know the numbers). I've heard it that cats are 'for women' and dogs preferred because it shows loyalty. A large percentage of women on dating profiles in my area write "I always stop to pet dogs when I'm out walking, I can't help it. Big plus if you have a dog!!"
I'm pretty sure it's cultural. In many countries dogs are expected to live outside as they're viewed as dirty. I believe in Middle Eastern countries cats are preferred to dogs.
I'm skeptical of evolutionary link here in terms of male desirability. Dog ownership might have something to do with a proxy for children and 'taking care' of a child-like creature (cats are more independent).