[quote name='Vinny']Even if you played the previous KH games, this would probably confuse you.[/QUOTE]
Hah! True story.
This game is fantastic, in case you're on the fence. If you like KH, it's a no brainer. But, if you just like action-rpg's, and the FF/Disney characters don't annoy you, you'll definitely think it's worth $20. It's a decent length game, and has many different gameplay types (kinda like mini-games that are good) as the series has become known to do. The drop mechanic is certainly either "love it, or hate it", but it doesn't ruin the game if you're not feeling it. I hate the drop mechanic, personally, but still love the game (it switches between characters way too fast, imho).
Give it a try. If you like the 3DS as a system, you won't be disappointed. I'd recommend watching a few vids & ending from KH1, or just a brush up in a wiki to enjoy the story (and it has a pretty decent internal knowledge database, at least enough to let you enjoy the game). Thanks, OP!