I have taken the plunge into OPML (Outline Processor Markup Language) [Wikipedia definition of OPML]. Alex Barnett created this screencast [Link to screencast] that describes what OPML is and shows us a really cool tool for creating OPML files. Here is a brief definition of of OPML from Wikipedia:
OPML (Outline Processor Markup Language) is an XML format for outlines. Originally developed by (Dave Weiner of) Radio UserLand as a native file format for an outliner application, it has since been adopted for other uses, the most common being to exchange lists of RSS feeds between RSS aggregators.
That tool is a web application called OPMLManager [Link to web application.] This is, as Barnett [Link to Barnett's blog] says, "really excellent." In Barnett's screencast he describes how he uses OPMLManager to create OPML lists of RSS Feeds. Well, that's cool, but that is not how I am using it. I am using it to create taxonomy's of information. One of the biggest weaknesses of blogs and other blog-like time based ways of presenting information is that it does not present an easy way of navigating information on subject hierarchy's. Yes, tagging does offer some of this, but tags only create ways of grouping information by keywords. Tags do not provide the kinds of tree-like constructs that a taxonomy does. This is something OPML does very very well!
OPML allows us to organize all of our content, and the content of anything else that can be linked to into hierarchies that make it easy to find information by topic. And, we get to choose the topics and those hierarchies can be linked to, shared and included in other people's OPML trees. This is so cool. So, using OPML I have created my own little Yahoo and other folks can plug into it. I love it, I have only just begun to organize my unorganized virtual universe. Here is what I have created so far: