I didn't read the original link posted that started this all, because it asked me to log in to something... so I'm not sure if he was being mean about it or not. Generally, though, I think physical attraction is an important part of a healthy relationship... not ALL of it, of course, but a PART. It doesn't necissarily mean the person is shallow, it just means they are more attracted to certain kinds of bodies. Sam, for example, can't stand very very thin women (which I like very much about him
). When I pointed to one of these women on tv and said 'I wanna look like THAT', he said that he'd still love me and stay with me, but that sex would be out of the question... he just wouldn't find me attractive.
I don't think asking your partner to lose a bit of weight is a very bad thing.. so long as it's done without hurtning the other person's feelings. I know a lot of women (myself included.. and probably men, too) are sensitive about weight and their appearance, but I don't think a spouse or partner should pretend that they will always be physically attracted to the other person no matter what if that isn't true.
However, I also think that everyone's own body is their own business. If you want to lose weight to make yourself more attractive, good. If you're happy with your body and not willing to change it for someone else, your partner will have to accept that, and continue loving everything else about you.