Upon looking further into this, I have found that vBulletin 3 actually already has built-in mechanisms for doing this sort of thing. It has to do with an external.php script, which doesn't seem to be working properly for JCF. It allows you to view latest threads using either JavaScript or RSS. I'm not sure if it allows latest posts within threads, but I'm sure it does.

Anyway, I'm not sure why the script isn't working for JCF. Maybe it's disabled or was crippled in a hack attempt? By hack, I mean an admin attempt to add/change a feature, not a hacker trying to be stupid.

-Nag