FAQ 80 (http://www.livejournal.com/support/faqbrowse.bml?faqid=80) currently reads "How do I add users and grant posting access to my community?" and addresses adding users to a community mostly from the point of view of a closed-membership community.
Recently, I've seen a couple of requests asking how you can send a user an invitation e-mail to join a community, where the community is not necessarily closed-membership.
So would it be worth adding "How do I invite users to a community?" to the title and mentioning inviting a bit more prominently? At the moment, it's rather hidden in the last two paragraphs.
I think most maintainers of open communities who ask this question think of it not as adding a user to a community but as inviting them to join, so perhaps the wording could be updated to reflect that.