In the claims section, the patent describes a chat system that uses a remotely stored buddy list, supports multiple statuses, broadcasts information about active gaming activities, displays notification of events including the arrival of new e-mail messages, facilitates transmission of player preferences, and enables users to communicate with each other either with voice or text messages. Keep in mind that this patent does not cover game-oriented chat in general; it specifically describes a console gaming chat mechanism that displays game information and uses a buddy list.
This isn't Nintendo's first chat-related patent. In February of this year, Nintendo was awarded a patent for a voice-to-text chat conversion system for video games that uses speech analysis to generate text with specific styles and attributes.