See the great lighthouse or drive through the sand and visit the pyramids. Race under water or in space, watching the stars passing by. Have some rest under the palms on the beach (watching the other karts overtaking you :) ). But don't fall in the volcano.
You can do a single race against other karts, compete in one of several Grand Prix, or try to beat the high score in time trials on your own.
Note: Now requires a 64-bit Intel processor
Full release blog post is available here