"Ad hominem" is only an appropriate term to use if I was saying that he was making an argument, but that his argument was wrong because of some defect in his character. It isn't just used for any time anyone mentions the other person in a conversation.

In this case, no argument was made. He simply said "The things I care about seem to be opposite of the things you care about". That's not an argument, it's just a personal statement. Even if ad hominem WERE the correct term, it would be even LESS appropriate here, because he was the one who brought up his own tastes in the first place.

EDIT: And to respond to the rest of your post, numbers like those are meaningless. Unless they're presented in a comparative context, they're very much like showing someone a graph without its axes labeled.

So for comparative purposes, Windows Phone shipped on that many devices. Great. How many Android and iPhone devices were shipped in the same period?