So, because of Google is into the whole social graph techno-hippie stuff Buzz works with open standards for moving information around. That means you can send your Tumblr into your Buzz feed as long as you make sure your public Tumblr page announces itself as belonging to the same person as your Google profile does. It’s actually not that hard, just add this line into the custom HTML for your theme (you can activate custom HTML without doing anything bad to your existing theme, this won’t change the appearance):

<link rel="me" type="text/html" href="http://www.google.com/profiles/your.username"/>

It can go right after/under this one (near the very top):

<link rel="alternate" type="application/rss+xml" title="RSS" href="{RSS}"/>

And you have to replace “your.username” with whatever comes at the end of your Google profile URL (usually just the first part of your Gmail address).

Once Google indexes a page of your Tumblr next (only a few minutes to a few hours, depending) you’ll magically have the option to add your Tumblr as one of your sites at the bottom of your Google profile editing page. Then when you go into Buzz you can select it as one of your sites to import from.

Neat!