Twitter takes a little getting used to. But once you get the hang of it--and if you follow the right people--it can be a lot of fun.
Some people use Twitter to share mundane information (i.e. when they last ate or slept) that no one really cares about except maybe a few friends. But others use it very effectively to share news, post fun/cool links, joke around, and add a human side to their professional business.
You can also ask a question (i.e. about a software problem or whether a portfolio site is any good), and within a couple of hours get several answers from people who follow your feed. Or, if you want you can strike up a conversation with just one specific person. If you have a blog you can also set each new blog post to automatically show up on Twitter.
The trick is to find the right people who's Tweets you find interesting or helpful. Follow them and emulate them, and you'll have a lot of fun with Twitter.
Here's some basic FAQ about Twitter:
A good list of Twitter do's and don'ts:
http://mobilemarketingprofits.com/78/tw ... ter-donts/