Updated at 2012-02-25T23:08:40Z: This has nothing to do with Blogger. It seems Google Analytics' tracking script will detect if you hold the account. If you do, then it shows you the interface. Here is a screenshot when I view the homepage of my blog:

When I was writing my previous post, I saw this after I hit preview button:

We found no clickthroughs for this page. Try adjusting the date range or select another page.

You got it perfectly right, Google Analytics! Because it's totally new post, how could you find click? If you do, either your are a fortune teller or something gone haywire.

But I don't mind this show up when I edit my old posts. It would be nice to know some statistics. Only it takes a few seconds to load the Google Analytics frame every time you hit preview button.