hi I think people in USA trust Msn more than Google. Personally from my point of view , I like MSN Ad center. It gives me plenty of traffic compare to Google with allocated budget,..
No I don's use MSN for search, but it is good for PPC, cheaper then Google and still good quality leads.
I just Use MSN for professional use and i don't like it . I like to prefer using Gtalk or yahoo messenger more than MSN.