For those of you on Twitter, I have some suggestions:
Neil Gaiman: A journalist from the UK turned full-time horror and fantasy writer. The author of such books as American Gods, Stardust and Anansi Boys.
Scott Lynch: The author of the Gentleman Bastard series of books as well as a volunteer firefighter. Has had struggles with depression, and posts relatively infrequently. Most tweets are about his personal life.
New York Time Books: The New York Times twitter feed on Books. Surprisingly enough, they link back to the New York Times.
Joe Abercrombie: One of the pioneers of a grimmer, darker vision of fantasy. Author of The First Law series.
Lev Grossman: A book critic who writes for the New York Times. Authored The Magicians, which has since been made into a popular television series on SyFy. I am currently reading his first novel, Warp.
John Green (and for bonus content, his brother Hank Green): The creator(s) of the vlogbrothers Youtube channel. John Green is a successful author, and these two head the self-proclaimed “Nerd-fighter” community of fans.
Jim Butcher: Author of The Dresden Files (an page-turning urban fantasy series) as well as The Codex Alera. Writes books that don’t stop moving, but he posts infrequently.
Fantasy Book Critic: The Twitter for the similarly-named blog. A resource for finding reviews as well as news.
Adam Whitehead: Creator of The Wertzone. A blogger from the UK who is diligent in his posting. For all your fantasy news needs.
Tor: The twitter of a UK-based publisher of specifically fantasy and science fiction stories.
Associated Press Oddities: Because everyone should follow and read these. It’s just interesting