MovieBob:
Irregardless of what you might think of me (if you've even read any of my stuff) I have a great deal of respect for you, but I think your a little off here on some of this.
Men and women aren't THAT differant when you get down to it. A lot of the Twilight images you've seen look like gay porn because on a lot of levels that is what they are. Women get off on that kind of thing the same way dudes get off on lesbians. It's a heavy subtext in a lot of the Paranormal romance stuff directed at women.
To put things into perspective there are plenty of images of erotic images of men directed at women. If you take a walk over a few aisles from the Sci-Fi/Fantasy/comics/RPing stuff in your local Waldenbooks you'll find the "chicks section" where they keep all the romance novels. Harlequins, etc... all of which feature pictures of attractive men in various erotic (though not overtly pornographic) poses with women, none of whom seem especially gay. Fabio (who is not aging gracefully apparently) became famous for posing for this kind of artwork, and allegedly Antonio Banderas did also before his film career. You'll also find artists like Julie Bell who draw all these perfectly formed guys without making them jump off the page as "wow, that's flaming".
Now, I'm not a photographer, but there is an artwork to that kind of thing that can make a picture say things without saying them. Use of light, color, lenses, whatever, but a good artist or photographer can convey a certain flavor of sexuality without being blatent about it. However it was done, those Twilight promotions ARE flaming. I get the same kind of impression from a lot of them, and honestly it's not some kind of discomfort due to the objectification of men or whatever because again I an look at artwork by guys like Frank Frazetta or Boris Valejo without getting the same impression. Ditto for other guys like say Van Damme showing off their awesome builds in photos for movies (well when they did movies like that which were good enough to actually see posters produced).
I tend to see it as the same thing when you take a couple of actresses and have them crawl over each other in a suggestive fashion or strike a suggestive pose which has nothing to do with the characters they play. The characters aren't lesbians but you as a guy are supposed to get that vibe. This is the same thing, and it's just shot that way, but in the opposite direction. You couldn't take a Frazetta picture of Conan or a Fabio shot and have it "pass" for the cover of a gay porn movie, but you COULD do that with some of the Twilight pics.
Just my thoughts, apologies about the length. I won't go off about fantasy art in general since this is long already. I just wanted to pretty much say that I don't think you or your friends are alone in getting that vibe, but at the same time I don't think anything is being projected onto that. Men have been as objectified as women if you know where to look and those promotions are stylized in a very specific way.