Geoff Holden has created XFN Graph, a Java based tool for creating visualization for XFN. Run the program, give it an URL, then it will spider the given web site for XFN links and provide you with a nice graph. You can instruct it to spider from one to four levels of XFN links. But in my case, it complained with an out of memory error when I chose more than one level :(. An odd error considering I have 1GB of memory, and it was nowhere near full.
XFN is an implementation of Internet based social networking, not unlike Friendster or Yahoo! 360. But unlike them, XFN is not confined to a specific web site, it is done in the World Wide Web itself. XFN is a Microformat, which means it is built on top of XHTML.
WordPress, the blogging software behind this site, supports XFN out of the box. As XFN gains more widespread recognition, any WordPress (or any XFN enabled blog software) user should take advantage of XFN in blogrolls. When search engines begin to understand XFN, XFN in blogrolls will replace social networking web sites (Friendster, Orkut, etc), at least in my opinion.