I find that the numbers are still very accurate. Although the first position is closer to the lower 40%-range rather than the upper (probably the universals, as tedster mentioned)
Doing some end-of-year analytics for one website I'm working on I can see numbers showing that going from #2 to #1 will give me an increase of about 100% to 130% of traffic. The reverse is also true, with a drop of 30%-50% going from #1 to #2.
Indented results and sitelinks also have a major impact on the click-through.
I have not had time to look further than the #1 and #2 keyword shifts... just to much work.