Andrew Grant-Adamson has [5 tests for a newspaper blog](http://www.wordblog.co.uk/2007/01/02/five-tests-to-avoid-blog-failure/)
  1. Does it do anything which cannot better be done in another section of the site?
  2. Does it develop the paper’s interaction with the readers?
  3. Does it gain a valuable audience? (A particular niche, readers who are new to the paper etc)
  4. Can you give the blogger sufficient time to blog successfully?
  5. Have you chosen a writer or writers who have the aptitude to blog successfully?

As he says “By no means exhaustive”, but it raises some interesting questions.