I often preview my post at blogger, to get an idea of how photos will integrate with text ( wrapping, etc ) but that preview doesn't always show me how the post will appear in Buzz. It seems that the page format at Blogger is a little different than the format in my Buzz stream.
When I'm posting manually from Buzz, I sometimes set the post to Null. Null Is a group I set up with no people in it. That way I can see how it will display, and delete it if I don't like the way it looks. No one sees it except me.
And then there are times I just plug URL's in to see how the pictures will display. I especially like posting Google Profile URLs to Null, just to see what photos Buzz will scrape from other people's Profiles. Sometimes it displays Picasa pics, sometimes it digs deep into their Buzz stream for interesting pics. Then I _X_ out.
I've left my Buzz set to post to Null. as I post this from Blogger. Hmmmm.....