As I have mentioned on other threads that brought this up, since CC is real-time, I find the PM's just as handy as what any chat room would be, if you don't want to have a conversation in the threads.
Just tonight, I've sat here and had a one-on-one conversation with Lorabell via PM on some of her cakes and other questions she had. The messages appear in my inbox instantly. I've been in chat rooms and I seriously don't see a big difference between those and what we have on CC.
The FB private chat box that pops up irritates me.