This is an interesting thread, because I feel like people can say what they feel the reasons why America is disliked by the rest of the world without it becoming a flame war.
Anyway, many of the reasons that I think the rest of the world dislikes America have been said above, but I'll say what I've noticed. I've lived in Canada for all my life, so that sort of gives me a different view, even if I'm physically very close to the US. I'll try not to list things that are strictly political, but are more behavioral, if that makes sense.
-This annoying notion that because the US helped in WW2 that somehow means that everyone else in the world has to kiss the US's ass, even if most of the people alive haven't served in that war! It's incredibly irritating to have the "well america saved the whole world so you must kiss our asses" conversation with someone. Yes, I would be very nice to someone who actually served in the war, but just because you happened to be born in the US does not mean that everyone must respect you. This brings me to my next point.
-Ignorance. I'm not saying that every American is ignorant, but that has been the face of America for eight years to the outside world. The US also has a huge problem with schooling in some areas, and this really doesn't help with the ignorance problem, since many young people are uneducated. It also doesn't help that many people are growing up in areas that are very isolated and don't show someone all different views of the world, or have parents that do not do that. I'm hoping that the general face of the US will change because of Obama, because face it, the rest of the world by far likes him. There's just something about him when I see him in other countries that shows that he really respects what the other world thinks.
-The blatant arrogance that some people show. So many people have this ridiculous opinion that "oh the rest of the world just hates us because they're jealous of us!" not only is that just stupid, but it's very immature. This isn't high school where you can say to someone who dislikes you "You're just jealous of me!", this is the real world, and honestly, not many people/nobody is jealous of the US. Everyone realizes that the US is a young country that grew very quickly and was successful, but that doesn't mean that they have to be jealous.
-Evangelicals. There are fanatic evangelicals pretty much everywhere, but there is a very high concentration of them in the US. Europe and much of the outside Western world in general are very liberal countries, and to see the amount of hate and bigotry spewing from these people and nobody taking action is very surprising. It's ignorant of anyone to think that all Americans are evangelical religious crazies, but when you watch the American news and nobody is saying "these people are absolutely insane and crazy", it is incredibly irritating. I just do not understand how anyone could allow these people to take away rights from others and to be in positions of power.
Anyway, there are my points. These are not strictly my views, this is just what I have observed from others in Canada, as well from others around the world. :)