i don't know where people get this belief that there has been proof that itsuki isn't gay.
yes, he said he was attracted to haruhi... in an alternate dimension. nowhere in the rest of the story does he do anything but hint at it, and he is definitely not portrayed as a womanizer. if he was, he would actually have some meaningful interactions with women.
it will be hilarious when itsuki is shown to be gay and the confession about haruhi in the alternate dimension was the author's trick. well, tanigawa wouldnt think of writing that anyways.