Okay, my two cents worth...
The way I see it (being somebody who's made more then a few celebrity cracks myself) is, that if you put yourself out there & choose to have a public life where the measure of your career is proportionate to other peoples opinion of you, both praise & criticism come with the territory. Yin with the yang & all that.
I think the majority of them would know that & are a bit thicker skinned then we give them credit to be & they wouldn't care what comments some people may say on boards like this.
I don't believe celebrities should be considered to be above criticism any more than the rest of us. They are, after all, only celebrities. They're not restoring peoples eyesight, they're not separating conjoined twins, they're not pulling people out of burning buildings or catching dangerous criminals & getting them off the streets, etc. And even people who do do all of those things aren't above criticism.
The main difference being we & they do is that they do it publicly (& they do get paid very well for it). I've been treading the boards as a Thespian for quite some years now &, on occasion, have seen some pretty unnecessarily insulting & completely irrelevant barbs in the local press by some critic with an axe to grind or baring some petty chip on his/her shoulders. You just take it as part of the business & get on with it. In fact, you have to be able to do that, I know a lot of people who burnt out because they couldn't.
Additionally, if any member of the public who goes to see a show I did, thought it (or I) was shit, has a blog & decides to say how much he hated it (or me) in his blog, that's his prerogative. At the same token, if he works at as a sales assistant in a department store & I (& his other customers) thought his service was poor, we've got just as much right to tell people in whatever environments our voice is heard.
You've even got shows on the tellybox like TMZ on GO! which exists solely to poke fun & ridicule celebrities. I reckon they laugh at those shows just as much as the rest of us, they laugh when they're having a go at someone else & enjoy the attention when they're having one at them...
But, having said all that, I think criticism about a celebrity says more about the celebrity & less about the attitude of the poster when it's done with a bit of humour.

There is one other interesting point in all this... By reading all the text posts, for many, this whole thread doesn't seem to be so much about a newsreader, but rather about a large pair of breasts. Enough to surmise that this thread probably wouldn't be so popular is Sammy had average size breasts. Is valuing someone for their breasts all that much better than calling someone else a peanut?
