But the team's management did release a statement Wednesday after Stern issued the suspension, saying they "fully endorse the decision" and Arenas' "recent behavior and statements…are unacceptable."
More and more athletes, politicians, celebrities and everyday Joes are employing the social networking site as a means to engage with fans, self-promote and stand on a virtual soapbox and shout their opinions. Twitter has over 58 million monthly users.
Twitter and other Web sites are a blessing and a curse, says Lee Rainie, director of the Pew Research Center's Internet & American Life Project.
"They have a new way to engage the public, their fans, and new ways to show a playful side of themselves…a way for them to bond even more deeply with their fans," he said. But "things that might seem private or more intimate, playful or spontaneous, appealing in one context, all of a sudden when they're tweeted out to a wide audience, could take on a different context."
Rainie said that the rules of the road on Twitter and other online sites are still being determined. "How much do I disclose? What's the tone of voice I want to have? How forthcoming do I want to be?"
Robert Thompson, director of the Bleier Center for Television and Popular Culture at Syracuse University, said that the ease and convenience of Twitter means that users often don't think through what they are posting online.
"That is one of the things that make this so appealing – it is so unprocessed. We're used to seeing before that we would only encounter celebrities or political leaders through press conferences, written statements, reports from journalists," Thompson said. "Twitter gets the sense that you are really hearing what they are thinking at any given time."
But, Thompson cautioned, that can be really dangerous for the person tweeting, "because people often say things off the cuff that are stupid and wrong and that can potentially get them in trouble."
One recent example of that is former Kansas City Chiefs running back Larry Johnson, who reportedly tweeted disparaging comments about his coach in a series of online messages that also included a gay slur. Johnson was suspended for two weeks and then ultimately cut by the Chiefs, who said it was in the best interest of the team to move forward.
One former professional sports team communications official said that sites like Twitter, Facebook and MySpace are "a professional publicist's nightmare – but a fan's dream come true."
"Don't publish anything on the Internet that you wouldn't want on a highway overpass," he said.
But not every athlete or celebrity embarrass their bosses with their online networking.
Cleveland Cavaliers center Shaquille O'Neal is the most popular athlete on Twitter, with more than 2.3 million followers. O'Neal uses the site as a way to engage with fans, frequently telling jokes, talking about sports and his games and getting in a little trash talk, too.
Chad Ochocinco of the NFL's Cincinnati Bengals may be one of the more engaging athletes on Twitter (his ID: OGOchOCinco).
Ochocinco, well-known for his on-the-field antics that frequently land him fines from the league, has over 600,000 on Twitter. He actively engages his diehards, soliciting advice on where to eat, buying some lucky fans tickets to Bengals games and keeping them up to date on his passion for video games and McDonald's.