[quote name='Vap']So how does the gameplay compare to puzzle quest? Is it like match 3 stones or is it something different?. I can't find a really good video that gives me a idea of what the gameplay is like.[/QUOTE]
Other people have given very good responses, but I'll chime in too: The game is sort of a blend of Panel de Pon/Tetris Attack, Meteos, and Magic the Gathering. It's turn-based, and you have a limited number of moves to arrange your characters to form vertical or horizontal lines, which either charge up attacks or create walls for defense. After attacks charge for a number of rounds, they launch at the enemy, and if you break through the defenses in that column and hit the enemy general, you tick off some HP.
The Magic reference comes not only in how you're trying to break through the other player's units, but also in how you choose your own "deck" layout; you have a small choice of types of units, each with different balances (some are weaker but charge faster; some are slower and have better defense; etc.). You can also stack attacks together, so if certain units attack in tandem they'll strengthen up. And you've also got Champion/Elite units, which rely on your basic units as fuel but can create massive chain attacks.
It's a hell of a game, and quietly one of the best DS puzzle-RPG hybrids to come out since the original Puzzle Quest (it's better than PQ, in my opinion). The XBLA/PSN version is coming out very soon with online multiplayer and generally better balance, but having the game in a portable format is also really nice, as it plays well in short bursts.