Often times, efreedom ranks higher than StackOverflow, and in some cases SO isn't even on the first page (for some reason the official source 'misses' with my search terms). In those cases, I open up the efreedom link and click through to SO. This seems to be happening more and more.

EDIT: I see that the extension actually redirects to SO. So in a way the presence of those sites when I wouldn't normally see SO results is a good thing. Nice.