Which of the tools covered so far seems the most useful to libraries

Personally, I think Twitter is so far the best I have learned that is applicable in the work environment. Being a cross between microblogging and instant messaging, the concept is simple. It is extremely powerful social tool. It is easy to connect with anyone and talking to each other at any time and any place and therefore you can send and receive messages, e.g. website. It is a useful tool in communicating with colleagues with regard to work and is fast and easy.