Eve is a male fantasy. "Male fantasy" is one of those terms whose meanings have become less and less precise as the result of too-specific associations (just as "racism" has become so attached to the racism of a particular group that we sometimes think it reasonable to use a term like "reverse racism" [which really only ought to make sense if we accept that one race is superior to another, right?]; just as "I'm ambivalent" has come to be roughly synonymous with "Meh," meaning "I don't like it too much," when of course in fact it most literally means "I have mixed feelings" [although there's no particular reason why the feelings have to be mixed] and is fairly well synonymous with the idiomatic "torn" and suggests a kind of non-totalitarian version of "doublethink"...meaning arguably the opposite of "so-so" insofar as the valence in it has everything to do with strength): yes, a chauvinistic or hypersexualized caricature of a woman is a kind of male fantasy, but just as not all racism is explicitly disparaging (many people would argue passionately [and incorrectly] that it isn't racist to say that black people are really good at music and sports or that Asian people are really good at Math and Science), not all male fantasies are explicitly demeaning. Indeed, many male fantasies put women not down in the dirt but up on a pedestal...
And the reason why male fantasies are problematic in stories not advertising themselves as male fantasy (no one, I think, would bother to complain about the "male fantasy" in a letter to the Penthouse Forum) (and of course this is also going to be the reason why racism is never OK even if it expresses itself as a compliment ["What, I just said they're good dancers!"]) is that they are, if not necessarily dehumanizing, then at least unconducive to any real kind of human sympathy.
Dehumanizing, human sympathy...going to have find different words, here, to talk about Eve. (Or maybe not: all of these movies rely heavily on the pathetic fallacy, and although these robots do have personalities "in the real world," to some extent we're making the leap as audience members...treating these robots not with the respect appropriate for a nicely advanced artificial-intelligence program but with the affection we generally reserve for human beings or for pets [and pets, too, of course, we humanize, as Pynchon points out in Mason & Dixon: "Once, the only reason Men kept Dogs was for food. Noting that among Men no crime was quite so abhorr'd as eating the flesh of another human, Dog quickly learn'd to act as human as possible..."].)
So here's the thing about Eve. (Could have called this post "All About Eve." Also could have called it "Tickle Your Rear." It's a free country.)
Eve is great to look at (not in an explicitly sexual way, but still); she can be reasonably cute in the way she behaves; and she's a bad-ass in a way that appeals both to the four-year-old boy (ka-POW!!! BLAMMO!!!) and to the man in which that boy resides like a pearl in an oyster. The pearl appreciates the explosions; the oyster gets off on getting slapped around and called names, maybe some candlewax. To be clear, though, I'm not just talking about nerds and fetishists: America's porno-Puritanism does prize attitude and tends to make its sex symbols somewhat untouchable—whether it's primarily to enhance the final conquest or to build punishment into the sinner's pleasure I can't say.
But is Eve a real character? Do we watch Wall-E and identify with her, really? Wall-E wants to hold her hand, Wall-E slowly wins her heart...but what's her personality? The closest we come to really seeing things from her perspective are the times when [MINOR SPOILER ALERT] we think Wall-E might be hurt (and her concern is just an extension of the audience's) and the time when she finally realizes how much he cares about her—but in neither case does she really transcend the love-interest role: in other words, her feelings about her "man" are themselves part of the male fantasy.
Giving a woman a big blaster does not guarantee that she's more than a sex object.
I liked Wall-E, and I don't mind male fantasies. But it's an interesting problem, innit?—the fully realized female character in a world still heavily dominated by the male sexual perspective.
...or do I have that wrong? Maybe male fantasies are also female fantasies in that what's really stimulating for women is reportedly "not the gender of the actor, but the degree of sensuality"...