Sure, Kart N' Crazy couldn't be more of a MarioKart rip-off if it featured an Italian plumber, but it's online, has experience and "nitros" to be spent on gadgets and gear, and hell, this is a really well put together trailer.
As for the confusion at the end where it's "Available Now" and "Coming Soon", we think the latter means the extra content that appears every two weeks. But it's definitely available, for free, from GOA.com. It's downloading now. Expect some thoughts in a bit. And mockery of the dreadful name. From a site called "Rock, Paper, Shotgun".