Overlapping Readers and Subscription Lists

I am always fascinated by the small world phenomenon, and was interested to see that it affects reading patterns as well - it's obvious when you think about it, in that bloggers with similar interests will have similar blogrolls and rss subsciptions/opml files, but fascinating nonetheless to find someone else (Karl Nelson) has been reading almost exactly the same articles as yourself. Pretty much 90% of the articles I have read over the past couple of weeks, which suggests to me very strongly that blogs support communities of practice, no matter how loosely/weakly tied they may be.