As promised in August, Audiosurf, formerly known as Audiosurf Air, is now available in beta form.
The sequel has one surprise new feature - Steam Workshop support for mods, game mods and skins. Some modes are already available.
Audiosurf is a racing rhythm action score attack game, which uses the players own music library and supports leaderboards for specific tracks. The sequel adds a new wakeboarding mode lets you distort songs to move in new ways.