Chat was on DalNet for a while, but I was having a hard time getting on so I gave chat a break for a while. The other night I decicded to try to get on early, like 7PM EST and I got on, only to see a note in the Topic that they had moved back to NewNet.
To answer your question, Yes people do use IRC for Chat, Use NewNet and go to "#bladeforums.com" to find it. Usually people start coming in around 9PM EST. If you're new to the room my suggestion is to say "Hello" and then let people know you're new and that you're from BFC, don't be shy because people that just come in and don't talk are suspect and could get the boot. Although chat gets some elite makers chatting there the conversation isn't always just knives and there's no guaratee it will always be fascinating, but like hanging out with the guys at a local pub if you hang around long enough it does become a habit and a cool place to hang out and chew the fat.