Blogging and the death of traditional media

As a librarian I have heard about the coming death of the book for years. Now that the internet is a major means of information dissemination, I have now heard predictions of the disappearance of newspapers and "expert" opinion with the rise of the blog. Radio National discussed this recently in the Philosophers Zone "The epistemology of blogging".
Having just looked up the meaning of epistemology in Wikipedia, I found the discussion rather interesting.

• What is knowledge? Well that is what the philosophers are for. As far as I can see (in a library) knowledge is anything any author has published, mainly non-fiction but that also encompasses fiction (literature).
  
• How is knowledge acquired? Knowledge is largely acquired through experience, reading and requirement. If you ask the year 11 and 12 students at the moment, knowledge is what will get them through their exams (required knowledge).
  
• What do people know? Lots of stuff but each person only knows a fraction of the whole and believes other people are either more knowledgeable or less knowlegeable than themselves, with various emotions surrounding this.
  

So how does blogging effect the acquisition of knowledge?? As far as I can see the blog is like a book. You choose what you want to read and think, respond to that information according to your background, culture and interest. And you do not assimilate or think about the rest.
Not enought time and brainspace to watch TV, Youtube and read the latest book about climate change simultaneously.
So I doubt blogging will change us very much. We will each filter our knowledge through our "rose coloured" tints. The internet is useful in that you can argue anything and find someone to support you very easily.
As wikipdia explains "Belief is a subjective personal basis for individual behavior, while truth is an objective state independent of the individual. On occasion, knowledge and belief can conflict producing "cognitive dissonance".