Lately Twitter has been getting a terrabyte’s worth of celebrity buzz.

After a tweeting addiction got pinned with the blame for John Mayer’s breakup with Jennifer Anniston, Mayer opined that posting on the micro blogging social network is “inherently silly and inherently dumb.”

He proceeded to put up a non-silly and fairly astute post on the subject of self-esteem.

“Living by the power of other people’s suggestion will slowly kill you. Genuine self esteem isn’t a roller coaster. It comes from within,” Mayer texted.

Look for esteem or something like it to end up in a new Mayer song.

Meanwhile Demi Moore’s Twitter wits may have helped save a life.

A distressed woman had sent the “Charlie’s Angels” star an ominous Twitter message that read: “Getting a knife, a big one that is sharp. Going to cut my arm down the whole arm so it doesn’t waste time.”

The alert actress and Ashton Kutcher spouse forwarded the terrible tweet to her 350,000 Twitter followers, adding this supplemental message: “Hope you are joking. Everyone I was very torn about responding or retweeting that woman’s post but felt uncomfortable just letting it go.”

Demi’s followers sprang into action and contacted the police who were able to find the woman and prevent the potential suicide.

“Thanks everyone for reaching out to the San Jose PD,” Moore later tweeted. “I am told they are aware and no need to call anymore. I do not know this woman…”

“It is my understanding that the situation was not a joke and that through the collective efforts here action was taken to provide help!” Moore added.

It just goes to show that social networks can be used for more than mere amusement.

They can be twitterly important and at times tweetastic.

BTY, I’m a twitterer, too, and if you’re so inclined please forward me your choicest news twips and H-tweets.

Twanks.

James Hirsen is a media analyst, teacher of mass media and entertainment law at Biola University and professor at Trinity Law School.