Skype got an extreme makeover and is now available in Windows beta for those so inclined. New features include direct access to SkypeCasts, which are cool if, um, useless at this juncture as well as some UI tweaks and file sharing extras.
You can also creat public chats and invite the world to talk with/at you about any topic. It comes with banning services for trolls. No word on a Mac version, but rest assured they’re working on it.