tl;dr: IRCv3 is a working group developing backwards-compatible extensions to the IRC client protocol, building on RFC1459/RFC2812. Shipped features include SASL authentication, server-side message timestamps (for better bouncer playback), account tags, instant away notifications, and message grouping. In-progress work covers standardized account registration, chat history access, automatic STS-style secure connection upgrades, Unicode nicks/channels, and client avatars.