Conversations, conversational units, and Twitter
A while back, Glyph wrote an article more or less decrying 'tweetstorms', which are more or less multi-tweet sequences of remarks on Twitter and suggested that they should be blog posts instead (he later added an important followup). On the one hand I sort of agree with Glyph. Twitter doesn't make it very nice to read long sequences of tweets, and when I wind up trying to follow such things I generally wish I could get them in a blog post, even if it was just a copy of all of the tweets. On the other hand, I think that 'no tweetstorms' is going too far, because it conjoins an arbitrary limit (Twitter's 140 characters) with what I think people want, which is basically one remark in a conversation.
(I admit that my ox is mildly gored here.)
Twitter is not exactly a conversation, especially when you are starting a series of tweets from scratch, but it is close enough that there's a definite crossover. In my own Twitter usage, sometimes I can get what I want to say into a single tweet, but sometimes really covering it requires elaboration or what I need to say is simply larger than 140 characters. But what all of these cases have in common is that they are what I consider a single conversational unit, for lack of a better term. Each of them is a single small-scale thought, and so they're all the sort of thing I might say as a remark in a back-and-forth conversation.
I think that people are happy to both read and make genuine remarks on Twitter, even if they go over 140 characters and thus have to be done through several tweets. In a normal, natural conversation, you should be reasonably short but no one expects you to speak in a single short sentence and then stop. A big tweetstorm is different, though; it's not a remark, it's a speech, and people can tell. If you're going to make a speech, that's when you should get a blog.
In practice it's probably more like the distinction between writing a single paragraph or a big multi-paragraph thing. Short runs of tweets are basically a single paragraph spread out across several tweets, while a big tweetstorm would almost always clearly translate to multiple paragraphs if written out in pretty much any other form.
(I find Twitter's 140 character limit interesting and even sort of fascinating because it so clearly affects how people write on it, myself included. And sometimes this includes not writing things when I can't find a good way to fit them into the confines of a tweet or three. I'm sure that all mediums affect what and how we write, but for me it's rare to feel it so clearly. For that matter, having the character count for pending tweets directly visible affects how I write them.)