Thanks for the replies! I asked a male friend who knows I'm H+ what he would prefer, and his thought was that he would prefer to have time to think about it without me being there in person, and since we already knew we were attracted to each other, it was likely that things could get hot and heavy before I found my moment to reveal, so might as well get that out of the way.
So I did! I drafted up a long text, had it proofread and edited, and then sent it off! Here's the text:
"I want to tell you something sooner rather than later...I have hsv-1, aka herpes. If you aren't familiar with it, I can tell you more about it, no question is off limits, but long story short, it is an STD and there is a 3-4% chance that you could catch it from me. It's not a big deal in my life and I'm on suppressive medication, but I like and respect you, and I want to be upfront about it before our relationship progresses any further so you can make an informed decision about how you want to proceed. I'd rather have told you in person, but you deserve the truth now and I think it's fair to tell you before you visit me."
Phew! What a terror. This was his response:
"I appreciate you telling me. Honestly, it doesn't change the way I feel about you at all. that is such a small thing that doesn't even come close to outweighing everything that is awesome about you."
Now, this guy is super easy-going and laid back, so can't promise the same results with everyone, but as nerve-wracking as it was, telling someone in person was far more painful, so I recommend early reveals.