One or two players can connect to Nintendo Wi-Fi Connection from a single console, and then select from Worldwide, Continental or Friend pools of players.
"Then you will be placed in a new group of people looking for a match, or you will join an existing group," says the website.
"When the latter happens you will become a spectator of that group's race currently in progress, as you wait for your turn to hit the track." We're quoting these bits because we don't fully understand them.
You can also see which Friends are online and then Create a Room or click Join Friend to gather people together. The Forecast Channel's globe graphic will then show the locations of the players present, and you can text chat using predefined messages, but not evil voices or sinister typing.
Online race-types mentioned on the site are Battle, Grand Prix and Teamplay, with the game host selecting race settings while the group itself votes for a track. No not sodding Rainbow sodding Road.
As we know by now, Mario Kart Wii also lets you install a Mario Kart Channel to the main Wii interface, which can then be accessed without disc in the drive. You can view stats for each track and compare results to Friends and other players, represented by Miis. There are also Competitions, similar to Mario Kart DS's Missions, set up by Nintendo on a regular basis.
It's also possible to race against Ghosts of other players, including Ghosts of rivals who are only slightly better than you. If you're shy, you can also choose not to share Time Trial Ghosts with the rest of the world.
Look out for Mario Kart Wii on 11th April and our full review nearer release.