Here's a list of 5 of the best blogs for writers (in my opinion), in no particular order.
1. Nathan Bransford
Nathan used to be a literary agent (and is currently a writer) and he offers all kinds of advice for people interested in the publishing world.
2. Pimp My Novel
Written by someone working in the sales department of a publishing house, this blog provided really unique insight into writing and how to improve novels.
3. A Newbies Guide to Publishing
J.A. Konrath is a legacy published author turned self-publisher. He offers advice and encouragment to people seeking the self-publishing route, along with interviews and all kinds of information.
4. Write to Publish
The owner of this blog runs a small press and shares all kinds of knoweldge about the writing world with her readers.
5. Fiction Groupie
This site is written by romance author Roni Loren, who offers all kinds of tips and tricks for writers.
Of course there are tons of other great sites out there. Feel free to leave your own favorite writing blogs in the comments!