1. You should be a fan of Istha. Why join othewise?
2. If you don't have a site, that's fine, but if you do and expect me to link you, I expect a banner or text link on your site, as well.
3. No negativity towards any group of people on your site. ANY. If you do, (and I check all of the sites) then you can still join, but I just won't link you.
4. NC-17 stuff is alright, as long as it's marked
5. I am excepting ff.net and LiveJournal accounts as the exception for not linking back for now. But it'd be great if you'd put up a text link!