What is interesting is to see that there is a clear division between Oracle employees and non- Oracle employees. There is also a mixture of oracle.com-based blogs and external blogs. It is also tough to see if these are Oracle or OTN blogs.
What is very cool is the widget which allows you to see a tag cloud of the most active bloggers.
What is even better is that you can change the timeline to see who has been most active over a ceratin date range. I find this is bvery useful to get a quick impression of how active the community is.
Ideas for SDN might include tag clouds based on category (might be easy to implement since most blogs are associated with 1 or more categories) or what about tag clouds from blog comments.