What are the major differences between the English dub and the original Japanese?

In my opinion I thought the English dub was really good. Obviously some differences between the Japanese and English version are how the characters sound. Also in the English version thee seems to be a little less swearing. Over all though it was pretty accurate.

I don't think there are any MAJOR differences, but there are minor, like the fact Haruhi sounds もっと見る boyish and it's easier to tell the twins apart due to the voices, I think the two minor-major changes were the opening and ending, many people were commenting on how poor they were and that the two main character's VA's should have sung them, but other than that, the dub's really enjoyable, I liked it, I actually got the jokes in the アニメ :)

well iknow that the girls voice is higher pitched i the japanese version and the lines are different cause the tv company thinks they are some what inapproite

i like the characters speaking japanese with english sub because there voice sound クーラー and cuter than english..(that's my opinion)

there are times when the english can't convert japanese words... i also think that english dubbers and the japanese differs completely in the way they deliver and express their feelings using words... but anyway, it's just my opinion and you'll be the one to decide.

If あなた enjoy a もっと見る cheesy and in your face アニメ with characters that are crazy over the top, I recommend the English Dub. Personally, I enjoy the Japanese Sub because the 芝居 is far superior and the characters are もっと見る down to earth, making the emotional AND funny scenes もっと見る realistic and もっと見る enjoyable. But that is my personal opinion. So if あなた like a 表示する with beautiful 芝居 and good comedic timing, Japanese Sub is the way to go.