Don't flame me
but:
I think the reason she is getting blasted for her weight gain is because she doesn't look "fine"...at least not for what her fans have come to expect of her. If she were a serious actress, she would look 'fine' and she wouldn't be in the headlines.
But she didn't get famous off her talent, she got famous from a killer figure with a so-so voice. Now she doesn't have that killer figure that teenage boys and young men want, she isn't a fantasy girl anymore, so her fans are bummed, and the media is laughing. Now, I don't think she deserves the mocking of course, but she got rich and famous for having little substance and big boobs, and the media loves to see someone come down. All this attention is what you sign up for when you get famous, and there's no such thing as bad publicity.
She's only got about 10-15 pounds to lose to get her old figure back. So, she'll go on a diet, maybe get a bit of lipo, and pretty soon she'll be back on the covers of magazines saying how she overcame adversity, lost all her weight through diet and exercise, and it will probably be timed before the release of her next album!