That is not really what I was referring to although that would be a duplication issue as well.

I was referring to some blog communities - not AR specifically - where when someone writes a blog post in their blog within the site - that post then also appears in the main "communty" blog that aggregates all of the blog posts made by members - no doubt to show how active the community is etc. In those cases Google seems to just list the version in the community blog while the member's personal blog does not get listed.

Active Rain just shows snippets of blog posts on their front pages not the whole blog post so one would think that duplication is not a problem - and it probably isn't. Members' blogs and posts do get listed in Google.

However, Active Rain does have its own issues. Most use Active Rain blogs because they are under the impression that the blogs rank well in Google. That is not necessarily the case.

Go to Active Rain and pick a member's blog at random - preferably the blog of a member who has been posting for a few years so Google has no excuse for not knowing where the posts are. Then pick posts at random going back from recent posts to ones that are years old. That is what I did and I found that there are more blog posts not even listed in Google at all than ones that are listed. (Use Google's "cache:" command for this - do not use the Google Toolbar's search box to search for a url as it bypasses the search engine and takes one directly to the url - which fools many into thinking a page is listed in Google when it is not.)

To me that says that if one is blogging there because they think their blog is going to rank well in Google they may be wasting their time. Many of the posts either will not be listed or will eventually be dropped from Google if they once were listed.

Not to pick on AR - other communities are worse. Just do some checking on your own. When others say that their blogs rank great etc.etc. - check it out on your own and keep checking every once in a while because small changes in a communities structure can have big consequences in Google (rarely for the better).

In my opinion the best place to spend blogging efforts is in your own properly set up Wordpress blog.

Great points, Doug. Initially I thought about making a big effort on AR to help promote my site, but now I will focus on a hosted wordpress blog.

It depends on what kind of information you are looking for.