Twitter has a lot more rules compared to other social media outlets, especially in regards to composition. All users have an 140 character limit per Tweet on Twitter. If you plan to re-tweet, you've got to keep it under 120 characters.
Not only is Twitter restrictive on how many characters you can use, there's lots of subtleties that make people mad. As a conscientious blogger, I just know you don't want your Tweets to undermine all the hard work you're doing on your blog.
In Edie Melson's book, Connections: Social Media and Networking Techniques for Writers she gets down to the nuts and bolts of the fundamental unwritten rules of Tweeting.