I have joined Twitter but can not really make up my mind about the service. Twitter is a kind of micro-blog, each message is maximum 140 characters. You can follow what your friends at Twitter post about and it is a quick and easy way to communicate.

Jason Alba has a post titled Twitter - Effective Networking Online? that is a good read on this phenomena.

Brent Hodgson sees Twitter from a business and marketing perspective in his post titled How Do You Profit From Twitter - Does Twitter Make Sense?.