Pretty entertaining, especially the musical scenes. Weirdly, Will Ferrell was one of the least enjoyable parts of the movie. I found his character dull - maybe that was the intent - but not in a likable way. Rachel McAdams and the actor who played the Russian singer were very entertaining.
There was a bit of a light satire of every nationality, but it seemed strange the movie went out of its way several times to say everyone in Europe hates Americans. Was that meant to appeal to a European audience ? It was like a turd in the punch bowl in an otherwise light enjoyable movie.