For a brief update on what libraries are doing with Twitter and other Web 2.0 tools, you can see David Lee King's slide show Communicating with Customers: Using Nothing But Bits and Bytes" at <a href="http://www.slideshare.net/davidleeking/communicating-with-customers-using-nothing-but-bits-bytes-presentation">http://www.slideshare.net/davidleeking/communicating-with-customers-using-nothing-but-bits-bytes-presentation</a> (slides 15-19 concentrate on Twitter); there is also a brief Infoblog overview of the various ways