Receptional_Andy - 10:24 pm on Apr 15, 2009 (gmt 0)

If you visit the example URL, you'll see a "redirect warning" asking whether you want to go to the target URL. Of course, such a page would create a new referrer. However, the only reason you see the interim page is because the destination doesn't match the checksum in the URL (Google added this test, incidentally, because phishers and the like were hijacking their redirect system to send people to convincing "google.com" urls).

There are only so many reasons I can think of why site owners would see the new referrer as essentially a redirect URL, like a bug in the click-tracking script, some kind of wacky interface changes on Google serps, or it's all a false alert ;)