1) Journalists use Twitter both to promote their own work and interact with colleagues, but are also adjusting their practices based on the evolving Twitter norms.
2) Different journalist beats use Twitter in distinct ways, with sports journalists more engaged with the public through retweets and mentions, while public affairs journalists more carefully retweet other media.
3) The study found fewer differences based on media type than beat, though online journalists were slightly more active than print, with all groups being more similar than different in how they use retweets and mentions on Twitter.