Can’t say that I’m really all that impressed. It wasn’t the shockingly better experience that I remember Google was when I first came across it. Some of the searches that I tested out seemed to be slightly better than Google, but I had to use contrived examples that I wouldn’t really use in everyday activities. These searches were simply designed to test Powerset’s strengths.
Couple this lack of noticeable improvement in search results along with the poor user experience due to site speed and I can’t say that I’ll be making the switch any time soon.