Thanks for the info.
When you "accept" a friend request, Facebook gives you a feature to add the friend in whatever list you want. It's right fucking after you accept someone. -_-
New Chat lets you send messages to them even if their off-line. Old chat couldn't do that. You'd have to go to 'messages' and do it there. New Chat also combined the Message section, in to the IM. So now if you message someone, it'll turn in to a IM by default. Get it? Do you comprehend?