Chat with friends, family and fellow gamers, for free
Discord - Chat for Gamers is seeing an impressive level of adoption by gamers and non-gamers alike. Its features are made for gaming, of course: it provides not just statuses, but a look at what games your friends are playing via your friends list.
It provides group chats, and they come with a lot of fun features. On the technical side, a lot of Discord's functions are handled server-side, which is great for many computers but means it lacks some functions (like the venerable Ctrl+F), and makes others (such as retrieving older messages) potentially slow.