Seth Godin is skeptical about using microblogs like Twitter.
If you've got 140 characters to make your point, the odds are you are going to be misunderstood (a lot). There may be nothing wrong with that, but you should be prepared for it to happen. And most of the time, people won't take the time to ask. They'll just assume you're an ignorant jerk and move on. If it's important, or controversial, I don't think I'd obsess about making it short.
By the way: Feel invited to follow my Tweet @ http://twitter.com/clienhardt