"The Directory is not automatically updated. If you are a new user or have changed your settings, it can take between 3 and 12 hours for updates to take effect."
I'd recommend adding this additional text (or something like it) as a second paragraph:
Also, please note that only Paid, Permanent, and Early Adopter Accounts have access to the Directory. This means that you will not be able to see yourself listed in the Directory if you have a Free Account. Free Users can, however, list themselves in the Directory so that other users with the proper account type can find them. Please see http://www.livejournal.com/support/faqbrowse.bml?faqid=123 for more information on the Directory and who can use it.
That paragraph a) links to the FAQ on the Directory and b) explains why Free Users won't be able to find themselves listed in the Directory. I think those are two worthwhile changes. Thoughts?