Absolutely! I mean, people feel a lot more of a sense of personal ownership over what's considered their "Personal space" in their journal and--IDK. You'll run into jerks and people who are tetchy, but such is life. Check our their profile, if you're unsure and being super-polite you can say "May I link?" but mostly, if people post something publicly there's the default understanding that anyone can comment/find it.

And I personally love it when users meet each other and talk in my comments (so long as it's not hostile, obvs.) It's great! More people!