Not much has changed with President Obama's trip overseas but he and wife Michelle were surely successful on the charm offensive. People from other countries are fascinated with the Obamas mostly because they don't really understand the U.S. except in terms of slogans they've heard. Just about anyone who lives here with eyes open is not at all surprised that an African-American was elected president but many, like me, are surprised that Obama was elected. (I thought it would have been more likely that somebody like Colin Powell, or Condaleeza Rice, or somebody of the centrist mold,would have been elected.) So the Obamas have a novelty factor going on, especially for the Europeans, who still don't know quite what to make of race, nationality, and culture.
When you talk to "foreign" visitors to the U.S., you notice a bit reticence among those who subscribe to the usual pre-packaged tropes and most are surprised at the degree of freedom here. Freedom isn't always the most comfortable thing in the world and that's why Europeans and others like less of it in their own countries.
However, even the severest critics of America are loathe to leave once they experience this freedom and opportunity .