Last spring, the Swedish national public service radio, SR, published an excellent handbook on social media for journalists in both Swedish and English.
The handbook discusses the strategics of why news organizations should be active in social media, and then focuses on the three strategical areas of dialogue, research and distribution of content. It also discusses some ethical dilemmas and legal issues, along with a section of private vs. professional use.
The handbook is available for free, as a pdf-file for download. You'll find it here. I highly recommend it!
On June, 21, Monika Djerf-Pierre and I presented our paper The social journalist at ICA 2013 in London. You'll find the slides (pdf) here).