Psych of Twitter

I have blogged for years, conversed on IRC, run e-mail lists and chat groups. Twitter is the first method I have seen where there was a severe limitation of expression. True in all the previous methods you could be brief ... but often people were not. Some suggest that the benefits of Twitter is that they force brevity. Is that a good thing? Or would it just be better to establish guidelines for posts to be as long as you really need to be? In a Psych Today article: the Psychology of Twitter.