They claim not to record any data, so there's no worry about gov't requests.
http://donttrack.us/
Interesting. This could become a real competitive advantage for them.
So they will really need something more compelling to get the average Joe (who make up the vast majority mentioned earlier), who always get his results from Google's first page, to switch from Google to DDG.
Yet, in the context of search engines, I don't see anything that could be more compelling than always getting the most relevant search results.