I have read many blogs and sites on Copyright and I must say I've found mixed information on this topic. Some say you should always copyright your work, others say it's not necessary, that the moment you write something it is yours. I'll always remember reading an agent's blog (Jane Judd) where she joked about our work probably not being that good to steal anyway, and even if she was joking, she is most likely right. However, as a writer, this issue affects me and I want to know I'm covered in the face of any events. I want to have all the details confirmed and the facts verified by a reliable source, that is why I'm going to keep a close eye on Jane Smith's blog who has declared an official Copyright day over at her place: http://howpublishingreallyworks.com/
I encourage you to visit it if you have as many doubts on copyright as I do.