Google Buzz automatically detects many of the sites associated with user’s Google profile using Social Graph API. Creating association manually is also possible–to do this, user has to include XFN link in
<head> element of the external site that points to the Google profile. More details here.
Now, as we know, owners of blogs hosted on wordpress.com cannot access or edit underlying templates, so cannot add the XFN link. Luckily, there’s workaround: wordpress.com supports Google Webmaster Tools verification. And, when you verify your wordpress.com blog with Webmaster Tools, it becomes associated with your Google profile!
So, step one: log into Webmaster Tools, add a new site, copy the verification key:
Step two: go to your wordpress.com dashboard, tools, and paste the verification key there:
Step three, four, five: Complete the verification in Webmaster tools, wait a bit, and your wordpress.com blog should then show up as suggestion in “connected sites” in Buzz!
This trick worked for me–let me know whether it works for you too!