I am a fan of Modnation and was excited to hear that it would be one of the launch titles. I own this game on both the PS3 and PSP and was looking forward to see what they did with it on the Vita. Sadly they didn't do much and didn't even do as much as the PSP did. The game advertises that it is cross game, which I thought meant one of two things, either you could race against people on the PS3 or you could save your game on the PS3 to the cloud and pick up there on your Vita. However neither of these were the case but instead it meant that you could download created tracks and carts that people had made on the PS3. This was a huge disappointment. At least you could still play online against other Vita owners and that would be cool but again no dice. The Vita version doesn't even have online play, something that even the PSP version had.
This game seems like it was put out to die and I had no idea why, until I heard that Sackboy was getting his own cart racer. Yes Little Big Planet is getting a cart racer and it looks like it will kill Modnation Racers. From what I've heard Modnation never took off like Playstation hoped it would so they are going to use the popular Little Big Planet to do another cart racer.
My take on this game is to stay away. While the game is fun if you can pick it up for a deal, it looks like a better cart racer is just around the corner. I wonder why Playstation even bothered to put this game out. Personally I'm thinking of downloading the PSP version on my Vita because it does have online play.