
It's a strange question, but one worth asking. Let's pretend we're not a member of either species, but rather an uninvolved observer from the Planet **56-AE.
EyesThough lacking an eyebrow, cats have much larger, more expressive eyes than a human. Their eyes come alive in the dark, adding a mystical sensuality that humans can't match.
NoseA cat's nose is a simpler, more elegant structure than a humans. In fact, human noses are often cited as an defeater of beauty. Cat noses are compact, tipped with color, and their nostrils are small, almost incidental, as compared with humans.
MouthCats lack full lips, so humans get the nod in this department. Human lips can range from full and pillowy, to narrow and vice-like.
EarsHuman ears are strange, unresolved open coils of skin leading directly into the skull. Smart women keep them covered. They seem slapped onto our heads, and with rare exception, never move. Cat ears are expressive and architectural, forming a lovely triangular shape, which they display with pride.
I went to college with a girl who was born without exterior ear flaps. Her replacement ears, while presentable, still drove home the fact that human ears are innately unattractive, a vestigal adornment crudely covering the inelegant open pits leading into our brains.
SkinAbsent thick fur, human skin is exposed to the elements, and eventually shows age lines. Cat skin is covered in fur and hides wrinkles. Plus, their fur invites touch in a way that human skin simply can't.
MarkingsHuman men can cultivate facial hair, but it can't compare with the deep, sophisticated patterns found on the lowliest tabby cat. Women apply makeup to their faces to accentuate their eyes, cheeks and mouth, an advantage a cat can never exploit, but still doesn't need.
WinnerCat! Is this possible? It ultimately comes down to their eyes and the ears. Some humans are a work of art.
All cats are a work of art.
(Anyone ever enamoured by a cat knows it's true.)
Still, I'm a man, and a woman's beauty rules the day.