Google has a page to test your sites' connectivity with respect to its Social Graph API.
Tim O'Reilly's sites see each other, the 2/3 is what I'm using as a benchmark for 'see'
I have updated three profiles and one webpage: Livejournal's Bio, About Me in Blogger and MySpace, and my personal webpage.
I can't get more than 1/2, 1/3, 1/4: http://tinyurl.com/2hte3a
I believe I am following Google's recommended XFN formatting of <a href="site" rel="me">Site</a>. MySpace reformats the links into msplinksCODE, but the links on the other sites show up as entered.
If you click through to see my pages, you will see my novice coding efforts, and hopefully find a quick correction. I would like to know why they don't 'see' each other, and be guided on how to fix my code.