As I've tried to explain in my comment to Repetition, Repeating, etc, this is a further response to the above as well as Steven's follow-up entry Redundancy all over again.
Many articles and pieces on blogging have been written from different perspectives and viewpoints. Different people blog for different reasons depending on their background, education, profession, current situations, world view, etc...
Most blog entries appear to be taking the form of responses and comments on other articles or blog entries, as well as links to relevant resources. Yet others, as has been explained in "Scholars Who Blog" in Chronicle of Higher Education have taken a form of research and academic publishing. Some are personal diaries. There are class discussion blogs, etc...
In any case, I don't believe bloggers should worry whether they are 'repeating' things across the blogsphere and apparently creating 'redundancy'. As you have noticed, I've put both redundancy and repetition within quotes to denote that perhaps it is paradoxical to talk of such functions in the blogsphere.
Individuals have things to say and blogs have opened another venue for doing so. Indeed a venue much different than before, because blogs and the corresponding blogging related tools provide an open communication and interconnectedness amongst individuals with similar interests.
For example, the new semester is about to start in September. Many graduate classes are conducted in seminar form and thus provide a platform for discussing interesting and relevant issues. For me, this will be another trigger point for writing blog entries. For one, writing about issues one is concerned ensures better understanding and comprehension of the subject. Maybe an interesting individual will comment on a blog entry with a twist that can bring new learning experience and a viewpoint not initially and readily available considering constrains resulting from previous experience and materials read. If nothing more, it is a learning experience that can expand beyond things immediately reachable.
One could argue that all of this could be done via discussion lists and posting on a regular personal page. Perhaps it could. However, there is an advantage to blogging vs. regular personal page because blog entries are usually fed into aggregators, read on regular basis by those interested, and interconnected with similar entries on other blogs. Thus, in a sense facilitating targeted information finding and learning.
As far as mailing lists are concerned, one difference comes in mind. While mailing lists are topic centric, blogs are multi topic centric, with more than one topic centers in a blog (i.e. categories). Thus, blogs provide more rounded profile of an individual expressing his/her opinions, ideas, and thoughts. In addition, besides blog entry interconnectedness, the categorization of entries can facilitate topic of interest interconnectedness. Following the traces (i.e. links) from one blog entry to another ensures multiple opinions as in mailing lists.
Needless to say, any such discussion whether facilitated through blogs and blogging, discussion lists, class seminars, or other discussion platforms, will result in same or similar issues being discussed more than once. But this is good as each instance has its own peculiarities and surrounding which makes it unique for the participants.
For this reasons, when viewed from participants' perspective, the issues of redundancy and repetition are non-issues. Even when viewed from the blogsphere ecosystem perspective repetitions of issues discussed tell much about the blogsphere itself and the topics/issues being discussed in particular.
how blogs effect each other
blogs, minds, documents, representations