On tweeting rather than leaning forward: I know so many people who do not really engage with the world, who don't treat colleagues much less strangers on the street as "real people." Techology allows for a certain total disconnect with reality as it is presented. Space is rent apart. Rather than being here in the room with the others who happen to be here, you are in your own private space with your friends and the social walls come down amidst the physical ones in a much, much stronger way than was previously allowable, or even practicable.
Of course, technology has not created this human tendency so much as exacerbated it. How many people will speak up and tell a stranger that they are doing something unfair or rude or annoying, rather than storing the experience away for future complaint? Certainly, some people will always pipe up out of smallmindedness and pettiness, always enjoying the chance to put others in their place. But there are not many who would speak up simply as a kind of social duty without thinking about it for a moment before or afterwards. "Excuse me, would you mind... Thank you." The end.
I suspect there is an edge of pleasure in some annoyances which people do not mind lingering in, for the thrilling moral outrage or even the simple self satisfaction it precipitates.

If you have a problem with someone, you ought to take your problem to that individual before appealing to the "tribal council"; to do otherwise risks damaging the other person for no reason. 

That's not the only reason to make discreet confrontation your first choice, but the other reasons are selfish and pragmatic, not ethical. Sniping status updates are in effect back-biting (especially if they're coy and cryptic), and from what I've observed, people who do a lot of that eventually earn the same treatment. You don't end up looking good; my suspicion is that it costs you more than the momentary novelty it offers.

Lulu, many possible directions to take this.

The rise of the blogger star. It’s interesting that Twitter didn’t raise many stars, (besides Ashton Kutcher and a few minor others). I wonder who will be the THINQon stars?

Penelope and Joseph focused on why she didn’t simply lean forward and ask Tavi to remove her hat, but it isn’t the hat which bothered her but Tavi’s celebrity. What bothered her was that Tavi got a better seat than her even though she is part of an established newspaper and Tavi is just a blogger.

The establishment of newspapers is disappearing, whether one thinks it is horrible or great, and the new stars can (and have to) stand on their own right. It is not enough to have been chosen by an editor for writing what they want you to write (and maybe for sleeping with them, or having family relations to them). The people can choose you directly.

One of the important aspects of Blogs, Twitter, and THINQon, is that they give people a voice where they didn’t use to have one. The writer for Grazia didn’t have a way to complain about Tavi’s celebrity and now she does. I see this as a positive aspect. Yes, it moves things to a public discourse, but why not? Tavi didn’t use to have a way to express herself besides seeming weird in her high school, but now she does. People didn’t have a way to speak with people about What does abstraction mean now?  but now one can find people all over the world to voice one’s opinions and hear other opinions about it. That’s a strong experience.

Is it good to let people speak? I think there is a fear that anything smart will be drowned out in a sea of nonsense and stupidity, but it also allows very smart and interesting things to be uttered which otherwise would have no place to be uttered and heard. Smart people who would otherwise stay silent or write in a newspaper read by 4 people, can now be read by many. It allows interesting people to find others, in a world which is moving to exist online.