To tweet or not to tweet, that is the question.

There’s no denying that Twitter is a social networking phenomenon. Let’s face it; once Oprah got on the Twitter train in April this year (2009), you knew it was probably something you should check out. Despite the fact that it was originally meant to help teens keep track of each other, it has grown up considerably over the past year. In fact, the vast majority of the network’s users are adults, not kids. Only 11% of Twitter’s users are between the ages of 11 and 17. Twitter has become much more than just another way to find out if your friend is at the coffee shop or if Ashton Kutcher is vacationing in the Caribbean. Talk to a teen, and they’ll probably tell you that Twitter is lame; they’d much rather go on Facebook to have longer chats, exchange photos, and play games.

So why the adult interest? The 140-character limit on posts would, at first, not seem to lend itself to anything more than “At the grocery. Lines are long.” But Twitter is about a lot more than just sending mundane messages into the ether. Though Kutcher beat CNN in a challenge to gain a million followers this spring, CNN acquired a ton of followers themselves. To date, they add up to over 2.8 million people receiving their breaking news. (Sure, Kutcher still has them beat at over 4 million followers, but that’s a lot of people who get instant updates without turning on the TV.) You don’t have to follow Britney Spears; there are news organizations like NPR and CBS, politicians like Barack Obama, John McCain, and Al Gore. Keep up with sports by following the Twitter feeds from the NBA, NFL, or MLB.

Though it may seem daunting to have countless tweets clogging your phone on a big news day, there are ways to narrow it down and even conduct research. Do a search through a Twitter aggregator so you can stay tuned into the news only you care to read about. Twist, Tweetizen, and Twitturly are three aggregators that can help you narrow your searches by topic, filter lists based on keywords and tags, form groups to facilitate discussion on a particular topic, and keep a tally of how many times the news story, video, or picture has been posted or retweeted. Got a product you think is going to take off? Check out the buzz on Twitter, invite people to join your group, it’s all free advertising.

There’s big business to be found on Twitter. More and more companies are jumping on the bandwagon to offer links to websites, coupons, information on new products, sale announcements, and more. There are rumors that advertisements will soon be included in the network. Twitter could charge a small fee and not have to look for content. It’s all provided for free by tweeters.

Twitter is even becoming a great place to find a job. Companies that are looking for social-media savvy employees have decided that the best way to find them is to go to the source. As job boards become more saturated, hiring professionals are finding more of what they want on Twitter, and at a cheaper cost than advertising on the regular boards. Many HR professionals will accept tweeted questions like “what should I wear to the interview?” and tweet back an answer in reasonable time.

It isn’t all sunshine and roses for Twitter right now, October numbers reported the first decrease of unique domestic users. It’s only 8%, which still leaves a whopping 19.2 million, but that’s enough to worry some investors. New features, like retweets and lists are in place to help reverse the trend. The question that has yet to be answered is why the drop, and is it truly a concern? It’s possible that it’s just a settling in period, especially with more youth users moving on to other social networking options. But with so many adults and businesses finding ways to work more efficiently and economically with this tool, it seems unlikely to fade away any time in the near future.

Twitter’s undeniable popularity is backed by more than fad and fancy. There are few options out there that allow you to make a brief, instant connection with potentially 19.2 million people in such an easy, cheap and fun way. Whether you are job hunting, researching a product, or just keeping up with your favorite sports team, Twitter has an application to help you achieve your goals for both business and leisure.