I am wonder when I seems like Google is reducing that number to only display four search queries! Yes, a WebmasterWorld thread has one researcher observing for search results that return sitelinks, in place of showing seven results, it is now displaying only four results.
This looks to be a test, I cannot retroflex the test myself but the screen captures seem lawful.
As we know that Google reduce search results from 10 to 7, but now Google took this down from ten to seven and now seven to four results.
I am not completely sure if Google has serious intentions of only displaying four search results on a page or not, but they look to be testing it.
The WebmasterWorld thread has one more image as well.