I wrote about the microblog namespace in Twitter Posts Don't Have Titles, a subject that could only interest someone who has been puzzling over how to do a Twitter-like streamer using RSS as the transport. The problem isn't whether or not RSS can do it, it can, the question is what to do about feed readers that don't understand. Answer: Let em figure it out!
For example, a lot of people wonder whatever became of their tweets. I have over 30,000 of them. Most of them are gone, poof -- into the ether. But some of them I have archived. I am determined that whatever we boot up now have archives provided for, in the base model.
With that info, you can loop over all the items I've pushed through this feed, going back to its inception. That's a built-in feature of Radio2. All Radio2 blogs have this feature.