Possibly one of the most internationally recognizable logos. Created by Milton Glazer in a rounded slab serif typeface; American Typewriter. It was initial created to promote New York tourism but has now become used as an worldwide brand. Apple used it to promote their first store in NYC by changing the heart to the apple logo.
I think in every country across the world you will find different takes on this logo, whether it is I (heart) Paris, London, Africa or the newly invented Michael Jackson with his famous pose in the heart. I am not the biggest fans of rip-offs of other brands and think that all the fame has lead to it being quite cheap and tacky.