Graphically, it is very similar to the first Supernova. You'll see a lot of the same characters like Rage and Jenny, some with some different outfits. Ever since they put the first video into DDR, I've enjoyed it. It seems like with every new release since then, they've added more videos. Supernova 2 piles them on. Granted, you'll probably have to get a friend to play for you so that you can watch things like Ashley Tisdale's video for He Said She Said without failing the song.
So let's be honest here, why do you really buy the new versions of DDR? It's the songs. There are 28 songs unlocked from the beginning. A large number of them you'll recognize from radio airplay, like Rock Your Body by Justin Timberlake, Suddenly I See by KT Tunstall, and even "oldies" like Take On Me by a-ha and Every Little Step by Bobby Brown. Of course, there's also your favorite classic DDR songs that you expect to see, like a Paranoia mix and a Trip Machine mix. No, I'm not telling you which mixes of them, you'll have to unlock and find out for yourself. There are at least 60 songs available total.