LOS ANGELES — It used to be that if you wanted to keep up with what your favorite celebrities were doing, you could either hang around their homes until a restraining order was issued or write them stacks of letters in hopes they would respond.

Now all you need is Twitter.

Chloe Sladden, director of content and programming for Twitter, has seen a real change in the past six months in how celebrities use social media. She says they've stepped up how they're engaging with audiences, promoting their projects and supporting causes.

Pauley Perrette (PauleyP), who plays Abbey Sciuto on "NCIS," was anti-social media to the point of naming her band Stop Making Friends. She proclaimed proudly on a YouTube video, "I am not on Twitter, I am not on Facebook."

That changed when Perrette was looking for help saving a women's and children's shelter that was about to close.

"I was freaking out. I talked to my pastor, I'm like, 'What do we do? What do we do?' And then my friend from church is like, 'You should start a Twitter account.' No, no, no, Stop Making Friends, that's not me, that's not me," Perrette says.

She finally gave in and through Twitter she raised $2.5 million in 48 hours to save the shelter.

Now Perrette considers herself a tweetaholic, especially when it comes to tweeting about "NCIS."

"Survivor" host Jeff Probst (JeffProbst) uses Twitter to promote his show, but he only tweets when the CBS reality competition is on the air to give insights to the show. He has to be careful not to reveal something prematurely.

"I don't know if I have tweeted anything inappropriate. The great thing about 'Survivor' is that I could tell you the answer and then challenge you to wonder if I'm telling you the truth or not. And that's always my out," Probst says.

Corinne Brinkerhoff (GoodWifeWriters), a writer on the CBS series "The Good Wife," started using Twitter to connect with fans give them an insider's view of the writers' room.

"We just did it on a whim. We wanted to see if anybody was interested. It was just thrilling, the immediacy of the response. It took a while to get followers, but then it sort of rapidly accumulated for us. I think just the immediate feedback, and the enthusiasm from people all over the world, it was just startling in a great way," Brinkerhoff says.

One problem with writers tweeting: Followers pay close attention. "The Good Wife" scribes heard about it when they misspelled the name of series star Julianna Margulies in a tweet.

"NCIS: LA" star LL Cool J (llcoolj) compares social media to having both radar and sonar.

"You see what is coming. You see what is on the horizon. You see the trends. You see what is out there floating around underneath the surface. You get to identify everything that is going on and respond to it," LL Cool J says. "It gives you the ability — if you pay attention and if you approach it with an open mind — to kind of hone and mold and adapt to what is going on out there in the world and how you're being perceived and how people are embracing what it is that you do and the products that you offer."

Distributed by McClatchy-Tribune Information Services.

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