What does that do to your stats if you're the number one result?
No idea. It doesn't show on my statcounter stats but maybe it shows in GA or my server stats. The only reason I noticed it is that I have a live chat client that tells me when someone hits the site realtime. Otherwise I would never have noticed it.
Sure it's not just a delay as realtime is not perfect?
No, without even clicking the result it does it. I think g1smd is correct - it's pre fetching.