Today's the first time I've heard of the term, from the news that Google acquired micro-blogging site Jaiku (a play on Haiku, by the way). I sort of like the idea, but don't intend on trying it. After all, most of my posts are fairly lengthy, like my last one, and I can't talk about integrating logical and stochastic artificial intelligence in 200 characters or less.
I like micro-blogging because of its spontaneousness. Instead, what I'll try to do is write down random thoughts in my Moleskine, and convert them into sentences, posts, essays later on.
That's what Moleskines are for.