Just got round to trying this. Game comes with a pack of non floral playing cards and some of the tricks are interesting like the crystal ball one. You can trick someone (who doesn't have the game!) into thinking the DS can tell whatever card you pick.
Most are just hit and miss though. There's one where get someone to draw a hand then pick an object. After tapping the hand, it will "magically" grab the object you want it to. Even without the game, I think someone can tell what the trick is.
Some of the single player tricks aren't bad. There's one where the DS gets you to shuffle some cards then it can tell whatever card you picked after following its instructions.