Microsoft’s New SSE Format: Bi-Directional RSS

I’m not entirely sure what to make of this myself, but I’m intrigued by Microsoft’s recent proposal for a new XML format called “Simple Sharing Extensions” (SSE). What SSE does is:

Simple Sharing Extensions (SSE) … defines the minimum extensions necessary to enable loosely cooperating applications to use RSS as the basis for item sharing—that is, the bidirectional, asynchronous replication of new and changed items among two or more cross-subscribed feeds.
For example, SSE could be used to share your work calendar with your spouse. If your calendar were published to an SSE feed, changes to your work calendar could be replicated to your spouse’s calendar, and vice versa. As a result, your spouse could see your work schedule and add new appointments, such as a parent-teacher meeting at the school, or a doctor’s appointment.
SSE allows you to replicate any set of independent items (for example, calendar entries, lists of contacts, lists of favorites, blogrolls) using simple RSS semantics. If you can publish your data as an RSS feed, the simple addition of SSE will allow you to replicate your data to any other application that implements the SSE specification.
SSE can also be used to extend other formats such as OPML.

So what does this enable, at least in theory? I can see services such as and Furl being enabled among smaller groups, where folks could post their bookmarks and share them via SSE in more distributed way. RSS feed collections — through OPML files — could also be collectively managed and published. What one person posts or edits would be visible to others, and so on. Does this create a Wiki-like service out of the more-or-less single-author blogiverse?
Lots more information is on Microsoft’s Frequently Asked Questions for Simple Sharing Extensions (SSE) page. The format, currently at version 0.9, is available under a Creative Commons license to enable experimentation and alteration. Very “Web 2.0” of them, if you ask me.