What is my Journal List?
If you decide you like someone, you can unlock their journal for posting, thus moving them from your Hot List to your Journal List, where you will have full access to posting to their LiveJournal. From then on, it's your job to introduce yourself and hope that sparks fly! They also won't show up in any more of your LJMatch searches.
[Update - 2300h]
Yes, it was poor wording. I sent her a calm panic note to please delete, but apparently, she's been panicked at all day... poor girl. =)
She's re-writing it now. You just get the URL to the person's LJ. I kinda thought maybe that at first too, but seeing as how everyone signs up with their LJ usernames, it would be obvious what the person's LJ URL would be. That combined with the words "unlock" and "full access to posting to their LiveJournal" was scary.