I noticed that G is changing frequently for the style they show results recently. something I noticed is:
1) in chrome, the auto complete drop down list is showing as an area below the search box, not drop down list. but still drop down list in other browser.
2) the site link is using huge font. so, if the site got site link and it is No.1, it occupies almost half the page.
3) the search result is kind of being rotate during the day. however, it does look like if G thinks your site is better, your site will have more time to stay on top.
the bad thing for 3) is: whenever I need write a report for clients, the client's ranking is below, once I finished the report, the ranking comes back,

I have to explain this to clients, which wasted lots of time.