I've never really paid attention to this field, but I just tried the sample queries from http://20bits.com/2008/05/12/powerset-launches-verdict-meh/ in Hakia. As far as I can tell, Hakia only answers the last question correctly without having to dig through the results.
To clarify, I didn't mean to say that the results returned by hakia don't contain the correct answer. For powerset/google the answer to many of the questions seemed to be right in the title or description of the results, without having to click on the answers, and that wasn't the case for hakia.