I never fail to emphasize to my blogging academy trainees that it is imperative for every serious blogger to read as many blogs as possible in their niche.
I am a blog marketing buff and I have subscribed to more than 26 blogs that focus on blog marketing. I am a fan of John Chow; I read Darren Rowse but they too don't cover every aspect of new internet marketing techniques like a few others.
For example, Viperchill.com maintained by Glen Allsopp is an excellent blog on internet marketing. His blog posts are highly informative and I love his subtle sense of humor.
Above all, he is shockingly honest and he doesn't even spare himself by admitting his mistakes that led to failures.