If the person actually knows they have herpes. It's very possible to have and not know. I'd guess the vast majority of people that carry it don't know they have it. Honestly, with both HPV and herpes, condoms aren't terribly effective. I also wonder if maybe some strains are worse than others, so that people who notice have a really bad strain? So, all things being equal? If anyone told me they had them, unless I REALLY already liked the person... I'd probably exit stage left. Nonetheless. If you know, you tell. Some people won't care. Others might have immune issues (non-HIV related) where such things could be dangerous.

But yeah, I'd rather know up front than freak out when they mentioned it months later.