Twitter - Success

I have finally joined up with Twitter and I tweet under the name marianb01, not many tweets so far.
Looking through I'm not sure that I like the idea of micro-blogging, it seems to be generating posts that don't have any relevance and appear to have been put up just for the sake of saying something.
Libraries could potentially use twitter to communicate with clients and promote events happening in the library; however I think they need to take care to ensure that each tweet is worthwhile otherwise it may annoy followers.